The first rule of Tuesday Group is: Do not talk to Freedom Caucus. The second rule of Tuesday Group is: Do not talk to Freedom Caucus.

Rep. Chris Collins the Upstate New York Trumpist moderate made that clear in March. "We have never negotiated with the Freedom Caucus," he said. "We will never meet with the Freedom Caucus." If they call, "just hang up," the Trump ally said.

Rep. Tom MacArthur broke that directive and dared to parlay with conservatives. To the "moderates," this is an excommunicable offense. The Hill reports that members of the centrist group are plotting to expel MacArthur for his actions.

Typically, one would expect the New Jersey Republican to receive praise for overcoming gridlock, especially considering the group's image of compromisers and deal makers.

"There is dissension in the ranks," one Tuesday Group member told Scott Wong at the Hill. "The Tuesday Group, to me, is a group of concerned, like-minded representatives who discuss issues, not negotiate positions on behalf of the group, but have meetings on Tuesday and have lunch and discuss the pending issues of the day."

The Tuesday Group is right to be angry at MacArthur. He didn't merely cavort with the enemy; he outed the Tuesday Group as undemocratic obstructionists.

During a recent closed-door meeting, the Hill reports, the group of centrists complained that MacArthur's negotiations helped bring conservatives on board with the healthcare bill. By trying to find common ground, he exploded the myth that the centrists are in anyway moderate.

But if MacArthur gets kicked out, he shouldn't feel too bad. It only means that when he promised to help repeal and replace Obamacare he was honest.

Philip Wegmann is a commentary writer for the Washington Examiner.