By Doina Chiacu and Susan Cornwell
WASHINGTON (Reuters) - President Donald Trump declared war on members of his own party on Thursday by threatening the political careers of conservative Republicans who helped torpedo healthcare legislation he backed, but was quickly told the lawmakers will not bow to "bullying."
In a Twitter post, Trump took aim at the Freedom Caucus, a bloc of the most conservative Republicans in the U.S. House of Representatives, indicating he would try to defeat them in next year's congressional elections if they continued to defy him.
"The Freedom Caucus will hurt the entire Republican agenda if they don't get on the team, & fast. We must fight them, & Dems, in 2018!" Trump said on Twitter.
Because Trump faces unified opposition by Democratic lawmakers, he cannot afford to lose many Republicans as he tries to get his legislative agenda through Congress, including healthcare, tax cuts and infrastructure spending. But keeping Freedom Caucus members happy without losing the votes of Republican moderates has proven tough.
Representative Justin Amash, a Freedom Caucus member from Michigan, shot back immediately at Trump in remarks outside the U.S. Capitol.
"Most people don't take well to being bullied," Amash told reporters. Asked if Trump's comments were constructive, Amash added: "It's constructive in fifth grade. It may allow a child to get his way, but that's not how our government works."
Since launching his presidential bid in 2015, Trump has shown little reluctance to assail fellow Republican political adversaries as well as Democrats, often in scathing terms.
Trump, a real estate magnate who touted his skills as a dealmaker in his White House campaign, previously accused Freedom Caucus lawmakers of snatching "defeat from the jaws of victory" with their opposition to Republican healthcare legislation he supported to replace Democratic former President Barack Obama's 2010 Affordable Care Act.
Trump went farther on Thursday. He equated members of his own party with the opposition Democrats, reflecting the extent to which he felt betrayed by the conservative lawmakers after the collapse of his first major legislative initiative.
Republican House Speaker Paul Ryan told reporters, "I understand the president's frustration," adding that he shared the frustration. Ryan said he was encouraging Republican lawmakers "to keep talking to one another."
The mistrust between the White House and hardline conservatives in Congress has called into question the next big item on Trump's agenda, sweeping tax cuts.
'BIG THINGS COMING'
Ohio Representative Jim Jordan, a co-founder of the Freedom Caucus, offered a more measured response to Trump's remarks and avoided direct criticism of the president. Jordan said Republicans need to figure out how to work together to confront looming battles including the federal budget, appropriations and raising the U.S. debt ceiling.
"Look, I'm not here to assign blame to anyone," Jordan told the "Fox & Friends" program. "I actually think we better get this right because there are a lot of big things coming."
"We better get it right now, figure out how we're going to work together to do what we told the American people we were going to do, and not just pass a bill that no one supports."
Republicans presented a unified front against Obama but have struggled to come together and support specific legislative proposals since Trump took office in January.
Freedom Caucus members opposed the Trump-backed healthcare legislation in part because they said parts were too similar to the Obamacare law it was supposed to replace. The called age-based tax credits in the bill intended to help people buy medical insurance an unwise new federal entitlement.
Ryan said in an interview aired earlier on Thursday he feared the Republican Party is pushing the president toward the Democrats so Trump can make good on campaign promises on an overhaul of the healthcare system.
"I don't want that to happen," Ryan told the CBS program "This Morning" program, referring to Trump's offer to work with Democrats.
Some conservatives outside the Freedom Caucus bristled at Trump's remarks about the bloc.
"I think he's still just negotiating," said Representative Thomas Massie, a Kentucky conservative who is not in the Freedom Caucus but close to some of its members.
Asked if this was a productive strategy by Trump to get Freedom Caucus members on board, Massie said, "We're on his side. We just feel like he's been misled on Swampcare," referring to the healthcare legislation championed by Ryan.
Amash depicted Trump as now beholden to the Washington establishment.
“It didn't take long for the swamp to drain @realDonaldTrump,” Amash wrote on Twitter. "No shame, Mr. President. Almost everyone succumbs to the D.C. Establishment."
On Tuesday, Trump expressed optimism about getting healthcare legislation through Congress despite the failure of the House bill last Friday, telling a gathering of senators "that's such an easy one" and that he expected lawmakers to reach a deal "very quickly." Trump did not offer specifics, and White House spokesman Sean Spicer on Wednesday said Trump's comments came during a "light-hearted" moment.
(Reporting by Doina Chiacu, Susan Cornwell Tim Ahmann, Amanda Becker, David Alexander; Editing by Will Dunham)