In the wake of his humiliating defeat in attempting to repeal and replace Obamacare, Donald Trump struck out at those he held most responsible, the unyielding far right of his own party, the Freedom Caucus. They held the decisive votes and withheld them because they said the bill before them didn’t go far enough in stripping bare the features of the Affordable Care Act.

The infuriated president threatened to punish the offenders by taking the unprecedented and very risky step of campaigning against sitting Republican lawmakers in primaries.

His first target apparently is four-term Michigan Rep. Justin Amash, according to a tweet from the White House by Trump’s former caddy and now special assistant for tweets. Amash is an outspoken member of the ultra-conservative Freedom Caucus, and the President would like to see the whole lot get in line or get out.

The Tweeter-in-Chief warned:

“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!”

Some of that was his emotional reaction to a stunning defeat, but Trump is well known for carrying grudges, and he could still target some in primaries that are only a year away.

It won’t be easy. Trump will be putting up his popularity against that of the hometown pols. Many won their seats last year by margins greater than Trump’s in their districts, and he has been steadily sinking in the polls. Those are very conservative, heavily gerrymandered safe GOP seats.

It’s unlikely any Democrats could win in those districts in November unless the Republicans knock each other out in such bloody primaries that voters want to send them a message of change.

Amash was called a “big liability” for Michigan in a tweet by Trump’s former caddy, Dan Scavino Jr., who now runs the White House social media operation, according to Politico. He tweeted last week urging Republicans to put up a primary opponent to dump Amash in 2018. Scavino wrote:

“.@realDonaldTrump is bringing auto plants & jobs back to Michigan. @justinamash is a big liability. #TrumpTrain, defeat him in primary.,”

Ironically, Scavino could be the one in trouble.

“[T]hat tweet, sent from Scavino’s personal Twitter account, immediately landed him in controversy as ethics lawyers called out Scavino for possibly violating the Hatch Act, a Depression-era law that regulates campaigning by government officials,” Politico reported.

One making that charge was Richard Painter, a former ethics attorney in the George W. Bush White House. “Fire this man NOW,” he tweeted.

Amash accused Trump of being a bully and fired back:

“It didn’t take long for the swamp to drain @realDonaldTrump. No shame, Mr. President. Almost everyone succumbs to the D.C. Establishment.”

Also on Trump’s hit list are North Carolina Rep. Mark Meadows and Ohio Rep. Jim Jordan, current and former leaders of the Freedom Caucus.