WASHINGTON, Aug 21 (Reuters) - President Donald Trump is likely to announce a modest increase in U.S. troop numbers in Afghanistan when he lays out his strategy on Monday for the war there, America's longest military conflict, a senior administration official said.
Trump will give a prime-time address to the nation at 9 p.m. (0100 GMT, Tuesday) to detail his view of the U.S. role in Afghanistan, an issue that vexed his two predecessors.
With Taliban insurgent forces no nearer to defeat, the most likely outcome is that Trump will agree to sending more U.S. forces as recommended by his senior advisers, the official said. Current U.S. troop numbers are about 8,400.
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The past 16 years at war in Afghanistan
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The United States and Britain on October 7, 2001 launched a first wave of air strikes against Afghanistan and President George W. Bush said the action heralded a "sustained, comprehensive and relentless" campaign against terrorism. Eyewitnesses said they saw flashes and heard explosions over the Afghan capital of Kabul in the first phase of what the United States has said will be a protracted and wide-ranging war against terrorism and the states that support it. The attack had been prepared since the September 11 suicide attacks on the United States that killed around 5,600 people. A U.S. Air force B-52 bomber drops a load of M117 750-pound bombs over a bombing range in the United States in this undated file photo.B-52s, B-1 and B-2 stealth bombers are some of the aircraft that were reportedly used in the attacks on Afghanistan. REUTERS/USAF-Handout KM/HB
Two Northern Alliance soldiers watch as the dust and smoke rises after
explosions in Taliban positions on Kalakata hill, near the village of
Ai-Khanum in northern Afghanistan, November 1, 2001. The Pentagon said
on Wednesday B-52s dropped heavy loads of bombs, a tactic known as
carpet bombing, on Taliban troops north of Kabul as a result of
improved tergeting intelligence, partly from U.S. special forces on the
ground. REUTERS/Vasily Fedosenko
U.S. Marine PV2 Eileen M. Schnetzko stands on guard at Bagram airport,
March 2, 2002. U.S. troops are based at Bagram, north of Kabul. There
are some 4,000 U.S. troops based in Afghanistan as part of the
international war against terrorism. REUTERS/Mario Laporta REUTERS
A U.S. special forces soldier (L) watches while Afghan militia wait in
line to turn in their weapons at a military base in Kunduz, Afghanistan
October 22, 2003. A long-awaited U.N.-sponsored project to disarm,
demobilise and reintegrate 100,000 soldiers across Afghanistan was
under way in the north, a key step to bringing eventual peace to this
war-torn country. The "New Beginnings Programme," which lets soldiers
exchange their weapons for jobs, began in the northern province of
Kunduz this week. REUTERS/Richard Vogel/Pool
A Chinook helicopter hovers over U.S. troops in the village of Jegdelic, about 90 km (56 miles) southwest of Kabul, Afghanistan, in this picture taken on December 24, 2004. A U.S. military helicopter carrying up to 20 American troops crashed during an anti-guerrilla mission in eastern Afghanistan on Tuesday, U.S. officials said. The fate of those on board was not immediately known. Picture taken December 24, 2004. REUTERS/Ahmad Masood Am/mk BEST QUALITY AVAILABLE
An Afghan boy looks at U.S. soldiers as they patrol a village near the town of Makkor, southwest of Kabul April 20, 2007. REUTERS/Goran Tomasevic (AFGHANISTAN)
A U.S. soldier works with a shovel as a vehicle is stuck in mud, some 70km south of Ghazni, southeastern Afghanistan April 23, 2007. REUTERS/Goran Tomasevic (AFGHANISTAN)
British and a U.S. soldiers control the crowd during medical assistance in Kabul February 26, 2008. U.S. and British troops provided medical assistance worth of $50,000 to the Afghan locals in Kabul on Tuesday. REUTERS/Ahmad Masood (AFGHANISTAN)
Sgt. William Olas Bee, a U.S. Marine from the 24th Marine Expeditionary Unit, has a close call after Taliban fighters opened fire near Garmsir in Helmand Province of Afghanistan, May 18, 2008.
REUTERS/Goran Tomasevic (AFGHANISTAN)
U.S. Secretary of Defense Robert Gates (L) and U.S. Army General David McKiernan, the top U.S. and NATO Commander in Afghanistan (R) listen to Afghan governors and local officials during their visit to Forward Operating Base Airborne in the mountains of Wardak Province, Afghanistan, May 8, 2009. Gates on May 11, 2009 replaced the top U.S. and NATO commander in Afghanistan, U.S. Army General David McKiernan, less than a year after he took over the war effort there. Gates said he asked for McKiernan's resignation and recommended Army Lieutenant General Stanley McChrystal, a former commander of special operations forces, to take over command of 45,000 U.S. troops and about 32,000 other troops from non-U.S. NATO countries. REUTERS/Jason Reed (AFGHANISTAN MILITARY POLITICS)
U.S. soldiers of the 2-12 Infantry, 4th Brigade prepare to tow a broken-down improvised explosive device (IED) detecting Huskie vehicle during a patrol in the Pesh Valley in Afghanistan's Kunar Province July 30, 2009. REUTERS/Tim Wimborne (AFGHANISTAN CONFLICT)
U.S. soldiers kneel during a memorial ceremony for Captain Daniel Whitten and Private First Class Zachary Lovejoy from Charlie Company, 4th Brigade combat team,1-508, 82nd Parachute Infantry Regiment at the Remote Sweeney FOB in Zabul province, southern Afghanistan, February 8, 2010. CPT Whitten from Grimes, Iowa, and PFC Lovejoy from Albuquerque, New Mexico, were killed by an IED on February 2. when on patrol in southern Afghanistan.
REUTERS/Baz Ratner (AFGHANISTAN - Tags: CIVIL UNREST CONFLICT MILITARY)
Canadian soldiers play table football under flashlights at a military outpost near the village of Bazaar e Panjwaii, in the Panjwaii district of Kandahar province August 8, 2010. REUTERS/Bob Strong (AFGHANISTAN - Tags: CONFLICT MILITARY)
U.S. Army medic Staff Sergeant Rahkeem Francis with Charlie Company, 6-101 Combat Aviation Brigade, 101st Airborne Division, treats an Afghan boy with a broken leg onboard a medevac helicopter near the town of Marjah in Helmand Province, August 19, 2010. REUTERS/Bob Strong (AFGHANISTAN - Tags: CONFLICT MILITARY POLITICS)
U.S. Army soldiers from the 2nd Platoon, B battery 2-8 field artillery, fire a howitzer artillery piece at Seprwan Ghar forward fire base in Panjwai district, Kandahar province southern Afghanistan, June 12, 2011. REUTERS/Baz Ratner (AFGHANISTAN - Tags: CONFLICT MILITARY IMAGES OF THE DAY POLITICS)
An Afghan shepherd walks with a flock of sheep past a U.S. Marines armored vehicle of the Weapons Company, 1st Battalion, 3rd Marines outside the Camp Gorgak in Helmand province, southern Afghanistan July 5, 2011. REUTERS/Shamil Zhumatov (AFGHANISTAN - Tags: POLITICS MILITARY ANIMALS IMAGES OF THE DAY)
First Sergeant Mac Miller from Comanche Troop 3rd Squadron 4th Cavalry lift weights as he exercises in Forward Operating Base Connolly in Nangarhar province, eastern Afghanistan, March 3, 2012. Picture taken March 3, 2012. REUTERS/Erik De Castro (AFGHANISTAN - Tags: MILITARY CONFLICT)
A U.S. Army soldier and a member of the Afghan Uniform Police arm wrestle prior to a joint patrol near Command Outpost AJK (short for Azim-Jan-Kariz, a near-by village) in Maiwand District, Kandahar Province, Afghanistan, January 28, 2013. REUTERS/Andrew Burton (AFGHANISTAN - Tags: POLITICS CIVIL UNREST MILITARY SOCIETY TPX IMAGES OF THE DAY)
A U.S. service member takes a "selfie" as U.S. President Barack Obama shakes hands with troops after delivering remarks at Bagram Air Base in Kabul, May 25, 2014. Obama, on a visit to Afghanistan, said on Sunday his administration would likely announce soon how many troops the United States will keep in the country, as it winds down its presence after nearly 13 years of war. REUTERS/Jonathan Ernst (AFGHANISTAN - Tags: POLITICS MILITARY)
Afghan children gesture at U.S. soldiers from Grim Company of the 3rd Cavalry Regiment as they stand guard near an Afghan police checkpoint during a mission near Forward Operating Base Fenty in the Nangarhar province of Afghanistan December 19, 2014. REUTERS/Lucas Jackson (AFGHANISTAN - Tags: CIVIL UNREST POLITICS MILITARY CONFLICT)
U.S. soldiers attend to a wounded soldier at the site of a blast in Kabul, Afghanistan June 30, 2015. At least 17 people were wounded in a suicide bomb attack on NATO troops as their truck convoy passed down the main road running between Kabul's airport and the U.S. embassy, police and health ministry officials said. REUTERS/Omar Sobhani TPX IMAGES OF THE DAY
A U.S. soldier keeps watch at the site of an explosion in Kabul, Afghanistan January 4, 2016. A large explosion struck close to Kabul airport on Monday, causing at least 10 casualties near to the area where a suicide bomber blew himself up earlier in the day in the latest in a series of attacks in the Afghan capital over the past week. REUTERS/Omar Sobhani
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Trump has long been skeptical of how the United States is fighting the war in Afghanistan, which was launched by President George W. Bush in October 2001 after the Sept. 11 attacks on New York and Washington. Trump announced a strategic review soon after taking office in January and has privately questioned whether sending more troops is wise, U.S. officials said.
"We're not winning," he told advisers in a July meeting, questioning whether U.S. Army General John Nicholson, who leads U.S. and international forces in Afghanistan, should be fired, an official said.
But Defense Secretary Jim Mattis has argued that a U.S. military presence is needed to protect against a continuing threat from Islamist militants.
Earlier this year, Trump gave Mattis the authority to set troop levels in Afghanistan, opening the door for future increases requested by Nicholson. The general said in February he needed "a few thousand" additional forces, some potentially drawn from U.S. allies.
The United States invaded Afghanistan and overthrew the Islamist Taliban government for harboring al Qaeda militants as they plotted the Sept. 11 attacks. But U.S. forces have remained bogged down there through the presidencies of Bush, Barack Obama and now Trump.
"I took over a mess, and we're going to make it a lot less messy," Trump said when asked about Afghanistan earlier this month.
Trump reached a decision on Afghanistan after lengthy talks on Friday with his top military and national security aides at Camp David, Maryland.
Officials cautioned that Trump could still change his approach before the televised speech, his third prime-time address to the country as president. He will speak from Fort Myer military base in Virginia, just across the Potomac River from Washington.
Afghan security forces have struggled to prevent advances by Taliban forces. The war confounded the Obama administration, which first committed an increase of tens of thousands of U.S. troops to reverse Taliban gains, then committed to a troop drawdown, which ultimately had to be halted.
U.S. military and intelligence officials are concerned that a Taliban victory over Afghan President Ashraf Ghani's government would allow al Qaeda and Islamic State’s regional affiliate to establish bases in Afghanistan from which to plot attacks against the United States and its allies.
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The best US military photos from 2016
The best US military photos from 2016
An Air Force F-22 Raptor flies over the Arabian Sea to support Operation Inherent Resolve, January 27, 2016.
(Air Force photo by Staff Sgt. Corey Hook)
Marine Corps Sgt. Josh Greathouse scans the area during a perimeter patrol in Taqaddum, Iraq, March 21, 2016. Greathouse is a team leader assigned to Bravo Company, 1st Battalion, 7th Marine Regiment, Special Purpose Marine Air Ground Task Force Crisis Response, for US Central Command.
(Marine Corps photo by Sgt. Rick Hurtado)
Navy Seaman Fabian Soltero looks through shipboard binoculars aboard the aircraft carrier USS Dwight D. Eisenhower in the Atlantic Ocean, March 25, 2016.
(Navy photo by Petty Officer 3rd Class Taylor L. Jackson)
USS Bulkeley receives fuel and cargo from dry cargo/ammunition ship USNS Medgar Evers during a replenishment at sea in the Persian Gulf, February 25, 2016. The guided-missile destroyer was supporting Operation Inherent Resolve, maritime security operations, and theater security cooperation efforts in the US 5th Fleet area of operations.
(Navy photo by Petty Officer 2nd Class Michael J. Lieberknec)
Navy Seaman Brice Scraper, top, and Petty Officer 2nd Class Alex Miller verify the serial number of a training missile on the flight deck of the aircraft carrier USS Ronald Reagan in the Philippine Sea, October 5, 2016. The Reagan was supporting security and stability in the Indo-Asia-Pacific region.
(Navy photo by Petty Officer 3rd Class Nathan Burke)
Navy Petty Officer 2nd Class Brianna Caballero maneuvers a harbor patrol boat to load it onto a trailer for maintenance on Naval Support Activity Bahrain, January 6, 2016.
(Navy photo by Petty Officer 1st Class Gary Granger Jr.)
Soldiers offload equipment and supplies from a CH-47F Chinook helicopter after landing on Kahiltna Glacier in Denali National Park and Preserve, Alaska, April 24, 2016. At 17,400 feet, Mount Foraker towers above.Air Force Maj. Steve Briones and 1st Lt. Andrew Kim fly a KC-135 Stratotanker aircraft over Turkey, January 6, 2016. Coalition forces fly daily missions to support Operation Inherent Resolve.Members of the visit, board, search, and seizure team for the guided-missile destroyer USS Gonzalez operate a rigid-hull inflatable boat in the Gulf of Aden, April 26, 2016. The Gonzalez was supporting Operation Inherent Resolve, maritime security operations and theater security cooperation efforts in the US 5th Fleet area of operations.
(Army photo by John Pennell)
Air Force Maj. Steve Briones and 1st Lt. Andrew Kim fly a KC-135 Stratotanker aircraft over Turkey, January 6, 2016. Coalition forces fly daily missions to support Operation Inherent Resolve.Members of the visit, board, search, and seizure team for the guided-missile destroyer USS Gonzalez operate a rigid-hull inflatable boat in the Gulf of Aden, April 26, 2016. The Gonzalez was supporting Operation Inherent Resolve, maritime security operations and theater security cooperation efforts in the US 5th Fleet area of operations.
(Air Force photo by Staff Sgt. Corey Hook)
Members of the visit, board, search, and seizure team for the guided-missile destroyer USS Gonzalez operate a rigid-hull inflatable boat in the Gulf of Aden, April 26, 2016. The Gonzalez was supporting Operation Inherent Resolve, maritime security operations and theater security cooperation efforts in the US 5th Fleet area of operations.Air Force Maj. Steve Briones and 1st Lt. Andrew Kim fly a KC-135 Stratotanker aircraft over Turkey, January 6, 2016. Coalition forces fly daily missions to support Operation Inherent Resolve.Soldiers offload equipment and supplies from a CH-47F Chinook helicopter after landing on Kahiltna Glacier in Denali National Park and Preserve, Alaska, April 24, 2016. At 17,400 feet, Mount Foraker towers above.
(Navy photo by Petty Officer 3rd Class Pasquale Sena)
Sailors move a T-45C Goshawk aircraft on the flight deck of the aircraft carrier USS Dwight D. Eisenhower in the Atlantic Ocean, February 5, 2016. The Eisenhower was preparing for inspections and conducting carrier qualifications.
(Navy photo by Petty Officer 3rd Class Anderson W. Branch)
The guided-missile destroyer USS Carney breaks away from the fleet-replenishment oiler USNS Big Horn after a replenishment at sea in the Mediterranean Sea, August 14, 2016. The Carney was patrolling in the US 6th Fleet area of responsibility to support US national-security interests in Europe.
(Navy photo by Petty Officer 3rd Class Weston Jones)
A Marine Corps MV-22 Osprey aircraft prepares for takeoff from the flight deck of the amphibious assault ship USS Boxer in the Pacific Ocean, August 26, 2016.
(Navy photo by Petty Officer 3rd Class Michael T. Eckelbecker)
Navy Petty Officer 3rd Class Kristen Neufeld performs maintenance on a Mark 38-25 mm machine gun aboard the aircraft carrier USS Carl Vinson at its home port in San Diego, August 18, 2016.
(Navy photo by Seaman Theo Shively)
Navy Petty Officer 3rd Class Brian Evans repairs an antenna system during a replenishment at sea involving the aircraft carrier USS Dwight D. Eisenhower, the guided-missile cruiser USS Monterey, and the Military Sealift Command combat support ship USNS Arctic in the Persian Gulf, September 2, 2016.
(Navy photo by Petty Officer 3rd Class Nathan T. Beard)
Sailors aboard the guided-missile destroyer USS Ross move ropes during a sea-and-anchor detail near Aksav, Turkey, January 7, 2016. The Ross was conducting a routine patrol in the US 6th Fleet area of operations to support US national-security interests in Europe.
(Navy photo by Petty Officer 2nd Class Justin Stumberg)
Navy Petty Officer 3rd Class Trevor Ellam signals to the fleet-replenishment oiler USNS Laramie from aboard the guided-missile destroyer USS Stout during a replenishment at sea in the Persian Gulf, October 14, 2016. Ellam is a boatswain’s mate. The Stout was supporting security efforts in the US 5th Fleet area of operations.
(Navy photo by Petty Officer 3rd Class Bill Dodge)
Marines depart a CH-53E Super Stallion helicopter aboard the amphibious-assault ship USS Makin Island in the Pacific Ocean, October 22, 2016. The Makin Island was supporting the Navy’s maritime strategy in the US 3rd Fleet area of responsibility. The helicopter is assigned to Marine Medium Tiltrotor Squadron 163.
(Navy photo by Seaman Devin M. Langer)
Navy Petty Officer 2nd Class Matthew Fulks motions to crew members on the flight deck of the aircraft carrier USS John C. Stennis in the Philippine Sea, February 24, 2016. The Stennis provides a ready force to support security and stability in the Indo-Asia-Pacific region.
(Navy photo by Seaman Cole C. Pielop)
The guided-missile destroyer USS Lassen patrols the eastern Pacific Ocean, March 10, 2016. The Lassen was supporting Operation Martillo with the US Coast Guard and partner nations within the US 4th Fleet area of responsibility.
(Navy photo by Petty Officer 2nd Class Huey D. Younger Jr.)
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"What we need to do is make sure that Afghanistan isn't a breeding ground for things that can come back and hurt us or our allies," Senator Tim Kaine, a Democrat and member of the Senate Armed Forces Committee, told MSNBC.
One reason the White House decision took so long, two officials who participated in the discussions said on Sunday, is that it was difficult to get Trump to accept the need for a broader regional strategy that included U.S. policy toward Pakistan before making a decision on whether to send additional forces to Afghanistan.
Both officials, speaking on condition of anonymity, declined to disclose Trump's decisions on troop levels and Pakistan policy before he does.
The difficulty in reaching a decision was compounded, the two officials said, by the wide range of conflicting options Trump received.
White House national security adviser H.R. McMaster and other advisers favored accepting Nicholson's request for some 4,000 additional U.S. forces.
But recently ousted White House strategic adviser Steve Bannon had argued for the withdrawal of all U.S. forces, saying that after 16 years, the war was still not winnable, U.S. officials said. Bannon, fired on Friday by Trump, was not at the Camp David meeting.
The officials said that another option examined was to shrink the U.S. force by some 3,000 troops, leaving a smaller counterterrorism and intelligence-gathering contingent to carry out special operations and direct drone strikes against the Taliban.
Proponents argued that it would be less costly in lives and money, and reduce the additional damage to U.S. special operations forces already strained by long-running engagements in Afghanistan, Iraq, Somalia and Syria. (Additional reporting by Idrees Ali in Amman and David Alexander in Washington; Writing by James Oliphant and Alistair Bell; Editing by Peter Cooney and Frances Kerry)