Back in 2007, Democratic presidential front-runner Hillary Clinton proposed that the U.S. "keep track" of all illegal immigrants in order to prevent future terrorist attacks, an idea that Republican candidates Donald Trump and Ben Carson have been scrutinized for in recent weeks.

Speaking at a campaign event in Iowa in November 2007, Clinton described policies that are quite different from the more liberal stances she now holds as she makes her second bid for the White House, reported The Daily Caller.

"So what are our options? I think you're not going to be able to get people to come out of the shadows if you say if they come out of the shadows then you're going to deport them. And so therefore you've got to give them some sanctions, penalties, fines, but bring them out so we know who's here," Clinton told the crowd, according to Breitbart.

"I feel really strongly about this because, you know, some of those hijackers who flew those planes into the World Trade Center, they came here legally and they overstayed so they were here illegally and we didn't have a clue. I want to know who's in this country. I want to keep track of them," Clinton said.

She continued: "So bring them out of the shadows. If they ever committed a crime, either in the country they came from or in this country, deport them immediately no questions asked. If they've been here and been lawful, then I think they've got to pay fines, they've got to pay back taxes, they've got to try to learn English, and they've got to wait in line, they can't get ahead of anybody else who's been here legally and waited. And they have to stay out of trouble, and keep working, and be law-abiding, and maybe in 10 or 15 fifteen years they can get legalization."

The video resurfaced after Trump suggested last week that the U.S. should "certainly" establish a database for Muslims. Carson followed up by agreeing that a database should exist, but said it should include all immigrants who come into the country, rather than just Muslims.

"If we're just going to pick out a particular group of people based on their religion, based on their race, based on some other thing, that's setting a pretty dangerous precedent, I believe," Carson said, according to Mediaite.

Clinton no longer supports many of those policies laid out in the 2007 video and has vowed to expand President Obama's amnesty program as she competes for the Hispanic vote with ultra-liberal Democratic candidate Sen. Bernie Sanders. On Wednesday, Sanders said he would bring back undocumented immigrants who have already been deported, reported USA Today.