WASHINGTON — Veteran Republicans are bailing on Congress in growing numbers, as their control of Washington fails to produce the unity or legislative successes party leaders wish for. With President Trump willing, if not eager, to buck fellow Republicans and even directly attack them, a number of lawmakers no longer wish to be involved.

The latest was two-term Rep. Dave Trott of Michigan, who said in a statement Monday that he’d decided after careful consideration that the best course for him was to spend more time with his family and return to the private sector.

In contrast to those diplomatic words was Trott’s most recent tweet, sent in mid-August: “I think America needs more unity and less divisiveness…meaning @realDonaldTrump should focus more on golf & have less press conferences.”

Trott joins a string of moderate Republicans, including Reps. Charlie Dent of Pennsylvania, Dave Reichert of Washington state and Ileana Ros-Lehtinen of Florida, not seeking re-election.

Each of these seats will be heavily contested by Democrats eager to take back control of the House, and rumors abound of other Republican retirements still to come. New Jersey’s Leonard Lance is weighing retirement, while another Michigan Republican, Rep. Fred Upton, is mulling a campaign for U.S. Senate, according to party operatives who spoke on condition of anonymity to discuss private deliberations.

Also Monday a senior Republican senator, Bob Corker of Tennessee, issued a statement indicating indecision about his future following a CNN report stating that the influential chairman of the Foreign Relations Committee had not yet decided whether to seek re-election next year. Although Republicans are hopeful Corker ultimately will decide to run — he already has $7.5 million in his campaign account — the senator was in Trump’s Twitter cross-hairs in August after criticizing the president’s response to the racially motivated protests in Charlottesville.

“Tennessee not happy!” the president declared after claiming that Corker was “constantly” asking him whether or not he should run again next year.

The developments have alarmed GOP operatives concerned that the trickle of retirements could turn into a flood unless congressional Republicans and Trump can come together and produce on their promises, particularly by overhauling the tax code. And, with Trump bypassing Republicans to make deals with Democrats, and encouraging primary challenges against sitting GOP senators, the retirement decisions also reflect concerns among some about whether they will get party support when they need it, especially with former Trump adviser Steve Bannon threatening all-out war on congressional leadership.

“There are some stability concerns in the party about whose team everyone is on,” said Josh Holmes, a former chief of staff to Senate Majority Leader Mitch McConnell, R-Ky. “Concerns about whether your party is really with you.”