The deadly attacks in Paris shifted the focus of Saturday's Democratic presidential debate to foreign policy and the United States' responsibility to help destroy ISIS.
PolitiFact examined several claims from the Des Moines, Iowa, debate.
Talking about what the United States should do to stop terrorism, Sen. Bernie Sanders, I-Vt., said, "We're spending over $600 billion a year on the military. And yet, significantly less than 10 percent of that money is used to fight international terrorism."
That rates Mostly False.
The Sanders campaign told us that he was talking specifically about the budget to fight the ISIS, which is about $5.3 billion.
But the fight against international terrorism is broader than that. The Defense Department includes its operations in Afghanistan in the fight against terrorism. And in 2015, the Pentagon said it will spent about $60 billion combating terrorism.
That's nearly 11 percent of the entire military budget and does not include billions of dollars more being spent by the FBI and CIA.
Former Maryland Gov. Martin O'Malley begged to be fact-checked when discussion turned to immigration.
"Let's say it in our debate because you'll never hear this from that immigrant-bashing carnival barker Donald Trump: The truth of the matter is net immigration from Mexico last year was zero. Fact-check me. Go ahead, check it out," O'Malley said.
We were up for the challenge and found O'Malley's claim to be Mostly True.
There is no perfect way to measure "net migration," but experts typically rely on data from the U.S. Census Bureau tracking the number of people living in the United States who were born in Mexico.
That data show that the number of Mexican-born Americans dropped each year from 2010 to 2013. And while it did increase in 2014, it remains well below the peak in 2007.
"O'Malley was mostly correct," said Alex Nowrasteh, an immigration policy analyst at the libertarian Cato Institute. "The population increased, but it was small. Mexican immigration certainly isn't surging anymore."
The margin of error is large enough that the actual number of Mexican-born people living in America in 2014 could be lower than it was in 2013.
Why is migration from Mexico to the United States slowing down?
Demographics is possibly the biggest driver. The birth rate in Mexico has fallen steadily since at least 1990 and now stands at 2.2 children per woman. Marc Rosenblum at the Migration Policy Institute said that translates into fewer people coming into the workforce.
Rosenblum told us that apprehensions at the border strongly suggest that fewer people are trying to sneak into the country. Data from the U.S. Border Patrol show a drop of more than 50 percent since 2009. It used to be border agents stopped over half a million people coming in from Mexico. Last year, it was about 230,000.
Clinton on wages
At one point, former Secretary of State Hillary Rodham Clinton was asked about how she would pay for such proposals as paid family leave. Clinton said she would not raise taxes on the middle class.
"I have made very clear that hard-working, middle-class families need a raise, not a tax increase," she said, adding that "wages adjusted for inflation haven't risen since the turn of the last century."
That's Half True.
To check her assertion about stagnant wages, we turned to figures collected by the Bureau of Labor Statistics.
We looked at figures for the third quarter of 2015. And to design the fairest comparison, we looked at third-quarter data for two different years — 1999 and 2000 — that could be used to describe the baseline "since the turn of the last century."
The data show that wages did rise between 1999-2000 and 2015, though not very much. Median weekly earnings of full-time wage and salary workers increased between 6 and 8 percent, depending on your starting point.
That's a rise, albeit not a huge one, as Clinton spokesman Nick Merrill pointed out when PolitiFact contacted the campaign.
Sanders on taxes
Sanders told debate moderators that he planned to raise income taxes on the rich. How much? He wouldn't say, but he guaranteed it wouldn't be as much as it has been in the past.
"We haven't come up with an exact number yet, but it will not be as high as the number under Dwight D. Eisenhower, which was 90 percent," Sanders said.
Sanders is talking about the tax rate that's applied to the last dollar earned. The U.S. tax system is based on brackets. The top marginal tax rate applies to the highest bracket. Income is taxed at higher rates as more is earned.
During the eight years of the Eisenhower presidency, from 1953 to 1961, the top marginal rate was 91 percent. (It was 92 percent the year he came into office.)
Sanders' claim rates True.
Louis Jacobson and Joshua Gillin contributed to this report. Read the full fact-checks at PolitiFact.com.