President Barack Obama was grilled repeatedly on Thursday on unmet promises of his 2008 campaign – facing some of the toughest questioning of his reelection effort to date.

At the Univision presidential forum on Thursday at the University of Miami, the president was pressed about his failure to achieve comprehensive immigration reform and on his administration’s decision to label last week’s violence at the Libyan embassy a terrorist attack.

The decision regarding the assault on the U.S. embassy in Benghazi, which killed U.S. Ambassador Christopher Stevens and four other Americans, brought increased criticism from Republicans on Capitol Hill, Politico reports.

When asked before the primarily Hispanic audience why the United States was not better prepared with increased security on the 9/11 anniversary, Obama discussed the incident in the context of a video that Muslims found offensive.

“This is obviously something that is used as excuse by some to carry out inexcusable violent acts on westerners or Americans,” Obama said, Politico reports, “and my number one priority is to keep our diplomats safe and our embassies safe.”

But earlier on Thursday, Obama’s press secretary, Jay Carney, said that the president considered the Benghazi attacks terrorism.

“We’re still doing an investigation,” he said, according to Politico. “What we do know is that the natural protests that arose because of the outrage over the video were used as an excuse by the extremists to see if they could directly harm U.S. interests.”

In other Univision questioning, Obama acknowledged that he had not changed the tone of Washington, as he had promised in 2008.

Read more on Newsmax.com: Obama Grilled on Failures at Univision Forum