Donald Trump's complicated and controversial history with 9/11

Two days after the terror attacks of September 11, 2001, a reserved and calm Donald Trump was asked in an interview to explain how it was possible that "two Boeing planes would be able to destroy the Twin Towers?" Without hesitation, the billionaire businessman attributed the destruction to "tremendous amounts of fuel," saying the buildings were hit with "more than anything could take."

No blame was laid at the feet of President George W. Bush, no peddling of conspiracy theories, no claims that if he were president the attacks wouldn't have happened. Instead, Trump stood poised in front of the Manhattan backdrop and championed New Yorkers as "strong and resilient," saying "they'll rebuild quickly."

Fifteen years later, Trump's relationship with 9/11 has evolved, and now perhaps more clearly resembles the Republican presidential nominee's current campaign -- controversy-laden and with a tendency to produce more questions than answers.

The 2001 terror attacks have come up multiple times over the course of Trump's presidential campaign, with the GOP candidate's remarks usually sparking outrage.

"The World Trade Center came down during your brother's reign. Remember that," Trump said during a heated exchange with Jeb Bush at a February primary debate.

This particular incident wasn't the first time Trump implied Bush was in some way to blame for the attacks. In October 2015, Trump told Bloomberg TV, "He was president, OK? Don't blame him or don't blame him, but he was president. The World Trade Center came down during his reign."

RELATED: Rebuilding the World Trade Center: 15 years after 9/11:

Trump's continued indictment of the former president drew ire from many in the Republican party. Jeb Bush called Trump's comments "pathetic," saying that his brother "kept us safe."

Fellow 2016 contender at the time Ben Carson also weighed in, calling the allegations against President Bush "ridiculous to suggest."

One area, however, where Trump and Carson see eye-to-eye are the billionaire businessman's controversial claim that he witnessed "thousands" of people "cheering" in New Jersey following the September 11, 2001, attacks.

Trump claims he "watched in Jersey City, New Jersey, where thousands and thousands of people were cheering as that building was coming down. Thousands of people were cheering."

While PolitiFact and The Washington Post conducted fact checks both concluding there's little to no evidence in support of Trump, Carson corroborated the claim saying he saw "the film of it," adding that he thought Trump's remark "was an inappropriate response."

Trump hasn't backpedaled on his attacks aimed at former President Bush, or his steadfastness regarding the existence of the infamous New Jersey celebration video.

He did, however, recently delete a tweet from 2013 where he commemorated the 12th anniversary of the September 11 attacks by saying, "I would like to extend my best wishes to all, even the haters and losers, on this special date, September 11th."

Trump's team removed the controversial tweet shortly after it started making the rounds online in 2015. When asked why the tweet was deleted Trump campaign spokeswoman, Hope Hicks told Business Insider "it is from several years ago."