Former Florida Gov. Jeb Bush, who has made it a point on the campaign trail to insist he's his own man, defended his brother during the second GOP debate Wednesday night. When questioned about having the same foreign policy advisors, Bush stuck up for former President George W. Bush, who was criticized for leading an invasion into Iraq after the terrorist attacks of Sept. 11, 2001.

"As it relates to my brother, there's one thing I know for sure: He kept us safe," the younger Bush said. "You remember the rubble? ... He sent a clear signal that the United States would be strong and fight Islamic terrorism."

The comment came after Donald Trump said he was the only candidate to push back against sending American troops to Iraq in the early 2000s. The real estate mogul said George W. Bush "gave us Barack Obama" and "was such a disaster those last three months that Abraham Lincoln couldn’t have been elected."

George W. Bush took office about eight months before 9/11, the al-Qaida terrorist attack that killed nearly 3,000 people in 2001. He was later accused of ignoring intelligence officials who had warned him in the weeks before the incident that leader Osama bin Laden planned to target the U.S.

Wednesday night, Jeb Bush elaborated on his foreign policy stance, calling for an effort to rebuild the military and follow a doctrine of "peace through strength." But it was Bush's retort about his brother that caught social media users' attention -- including that of singer John Legend.

How do you get to say you kept America safe when you presided during 9/11? That's a major asterisk — John Legend (@johnlegend) September 17, 2015

wait, jeb knows that 9/11 happened during Bush 43, right? and that Osama was captured during Obama’s administration, right? — a classic dan (@dcseifert) September 17, 2015

"My brother kept us safe." - Jeb Bush still hasn't been told about 9/11 #GOPDebate — John Fugelsang (@JohnFugelsang) September 17, 2015

The problem with Jeb Bush saying his brother "kept us safe" is that more Americans died in Iraq & Afghanistan than in 9/11. — Nicholas Kristof (@NickKristof) September 17, 2015

The much-awaited second GOP debate was sponsored by CNN and held Wednesday night at the Ronald Reagan Presidential Library in Simi Valley, California. Texas Gov. Rick Perry, Louisiana Gov. Bobby Jindal, former Pennsylvania Sen. Rick Santorum, South Carolina Sen. Lindsey Graham and former New York Gov. George Pataki faced off at 6 p.m. EDT, but the top 11 candidates made the primetime showdown at 8 p.m. The lineup included the so-called "winners" of the first debate -- Trump, former CEO Carly Fiorina and neurosurgeon Ben Carson -- as well as Bush, Texas Sen. Ted Cruz, Florida Sen. Marco Rubio, Ohio Gov. John Kasich, Wisconsin Gov. Scott Walker, former Arkansas Gov. Mike Huckabee, Kentucky Sen. Rand Paul and New Jersey Gov. Chris Christie.

Trump led the polls heading into Wednesday, riding on the support of 27 percent of Republican primary voters, according to a CBS News/New York Times survey. Carson was in second place, having jumped from 6 percent last month to 23 percent Wednesday, with Bush, Huckabee and Rubio tied for third.