The Pentagon barred the senior Democrat on the Senate Intelligence Committee from making an oversight visit to a military spy agency.

Armed forces off the coast of Venezuela began a military campaign against alleged members of a drug cartel without any authorization from Congress, and without notifying key members.

The White House informed Congress it planned to use a rare maneuver to skirt a vote and cancel nearly $5 billion in foreign aid funding that lawmakers had already approved, the latest escalation of its campaign to undercut the legislative branch’s spending powers.

And just a month after senators had confirmed her, Robert F. Kennedy Jr., the health secretary, ousted the director of the Centers for Disease Control. He also put forward changes that would effectively restrict access to Covid-19 vaccines, after pledging to senators during his own confirmation hearings that he would not make it more difficult.

The Trump administration continues to erode the power of Congress, trampling on its constitutional prerogatives in ways large and small. Through it all, Republicans in charge have mostly shrugged — and in some cases, outright applauded — as their powers, once jealously guarded, diminish in ways that will be difficult to reverse.

In recent weeks, G.O.P. leaders have looked on passively as the president has fired a litany of agency leaders whom senators worked for weeks to confirm, from the C.D.C. to the Internal Revenue Service to the Federal Reserve.