Eliza Collins

USA TODAY

On Thursday, President Trump threatened to defeat members of the Freedom Caucus in the 2018 midterm elections. So what is the Freedom Caucus, and why is the president of the United States threatening to defeat members of his own party? Let's start from the beginning:

How did we get here?

The Freedom Caucus, a group of hardline conservatives in the House, was one of the critical forces in defeating the Obamacare repeal bill that Republicans tried to bring to the House floor last week. The group of far-right Republicans spent weeks in negotiations with Trump and the White House and even got some conservative provisions added to the legislation. But in the end, most of them decided it wasn’t enough and said they’d vote against the bill.

That was a big problem for the Republicans, who could only lose about 20 votes. Plus, rewriting the bill to woo Freedom Caucus members led more Republican moderates to jump ship. In the end, about a dozen mainstream Republicans and the majority of the Freedom Caucus said they wouldn’t back the bill. Because no Democrats were expected to vote to repeal their health care law, Republicans had to abandon it last week.

So who exactly is in the Freedom Caucus?

That’s a tough question. We know that membership is somewhere around three dozen people and all-male. But we don’t know the name of every lawmaker in the group because the Freedom Caucus doesn’t make membership public. However, many members are happy to tout their membership. Rep. Mark Meadows, R-N.C., is the group’s chairman, and he’s often accompanied by Rep. Jim Jordan, R-Ohio, who was the former chairman, and Rep. Raul Labrador, R-Idaho.

Some other members we know of: Alabama Reps. Mo Brooks and Gary Palmer; Arizona Reps. Trent Franks, Andy Biggs, Paul Gosar and David Schweikert; South Carolina Reps. Mark Sanford and Jeff Duncan; Texas Reps. Joe Barton and Randy Weber; Michigan Rep. Justin Amash; Virginia Rep. David Brat; and Florida Rep. Ron DeSantis.

What’s their relationship like with Trump?

Until Trump turned his Twitter on them this week, most members of the Freedom Caucus were actually pretty close to the president. Meadows was an early Trump supporter during the campaign, and the two talked frequently. When it came time to negotiate on the health care bill, the Freedom Caucus decided to go around House leadership and work directly with the White House. The group was brought in for multiple meetings with Trump, Vice President Pence, Health and Human Services Secretary Tom Price and Office of Management and Budget Director Mick Mulvaney, who was a member of the Freedom Caucus before he joined the administration.

But all the high-powered courting wasn’t enough. Most members of the group never got on board with the bill. Trump originally did not blame the group, saying Friday after the bill collapsed, "I'm not betrayed. They're friends of mine. I'm disappointed because we could've had it. So I'm disappointed. I'm a little surprised I could tell you. ... You know this is a very hard time for them."

But over the weekend he turned against them.

On Sunday, Trump tweeted that the Freedom Caucus had helped save Planned Parenthood, and Monday he tweeted that they were able to "snatch defeat from the jaws of victory."

Where did they come from?

In 2015, a group of conservative lawmakers decided that the original conservative caucus in the House, the Republican Study Committee, had gotten too big and wasn’t conservative enough, so they broke off and formed the Freedom Caucus.

DeSantis, who was one of the founders, described the goal of the caucus as seeking to "provide a voice for those who are frustrated that Washington, D.C. does not represent their values." This is part of the reason many in the group were big Trump backers — they felt like he shared their "outsider" roots.

Have we heard of these guys before?

Yes, the Freedom Caucus was one of the driving forces behind former House speaker John Boehner, R-Ohio, resigning back in 2015. They were unhappy with Boehner compromising with President Obama and Democrats. The Freedom Caucus had no problem opposing their party’s leader and threatened to use government shutdowns as a negotiating tool. Eventually Boehner decided he was done trying to manage the unruly group and announced his retirement.