THE BURNED OVER DISTRICT

Presidents are allowed to have hairball ideas and the president's party will generally voice support for them, even if they have reservations and don't actually follow through. Up to now the Republican Party has voiced support for Mango Mussolini's hairball ideas but only voted for a few that they approved of, the balance of their efforts going to stifling the Democrats. Now Mango's naked power grab with his fake national emergency declaration has left the Republicans with their collective nuts in a salad shooter.

Senator Shelley Moore Capito, Republican of West Virginia, spent the last two weeks hammering out a deal on federal spending and border security with colleagues from both parties, reassured by a sense that Congress was finally asserting itself as a civil, stabilizing force.

The feeling did not last. On Friday, President Trump mounted one of the most serious executive branch challenges to congressional authority in decades, circumventing Congress with an emergency declaration. It would allow him to unilaterally divert billions of dollars to a border wall and presented his Republican allies on Capitol Hill, who labored on a legislative compromise, with the excruciating choice of either defending their institution or bowing to his whims.

The president’s move left Senate Republicans sharply divided, and it remains to be seen whether they will act collectively to try to stop Mr. Trump or how far into uncharted territory they are willing to follow a headstrong president operating with no road map beyond his own demands.

“With him you always have to expect the unexpected,” said Ms. Capito, speaking on the phone from her kitchen in Charleston, W.Va., exhausted from a week of late-night talks at the Capitol.

The Republican resistance to Mr. Trump’s emergency declaration was much more pronounced in the Senate than in the House, where a few Republicans — in the minority but more closely aligned to Mr. Trump — groused. But most of the conservative rank and file embraced it.

After threatening to kill the spending compromise needed to keep the government open, Mr. Trump opted to cite a national emergency to pry loose additional funding to build a wall longer than the 55 miles in the bipartisan agreement. It was the divisive step that Senator Mitch McConnell, Republican of Kentucky and the majority leader, Ms. Capito and most other Republicans in the Senate had forcefully urged him not to take, because it would establish a precedent they feared future Democratic presidents would use against them.

The decision left Mr. McConnell, a professed guardian of the Senate’s prerogatives and power, joining with Mr. Trump in supporting an executive branch end run greater than any of the incursions into the legislative process he often accused President Obama of pursuing. Fellow senators said Mr. McConnell, a former member of the Appropriations Committee, was unhappy with the declaration but saw it as the only way to pass the spending bill.

Some top Republicans, led by Mr. McConnell, pivoted quickly to say they supported the president’s action because it was the only option left to him after Congress failed to meet his demands for wall funding. Mr. McConnell has even begun offering the president strategic advice on how best to push his plan, aides said.

But Mr. McConnell is also warning Mr. Trump of the damage it could inflict on the party heading into the 2020 elections. Other Republicans portrayed it as a gross violation of the constitutional separation of powers, a blatant disregard by the president for Congress’s fundamental role in determining how federal dollars are spent.

“He is usurping congressional authority,” Senator Susan Collins of Maine, a veteran member of the Appropriations Committee, said in an interview. “If the president can reallocate for his purposes billions of dollars in federal funding that Congress has approved for specific purposes and have been signed into law, that has the potential to render the appropriations process meaningless.”

Several other Senate Republicans publicly and privately joined Ms. Collins in describing the move as a flagrant breach of congressional jurisdiction and a dangerous precedent. Their numbers raised the clear possibility that enough Republican defectors could join with Senate Democrats to provide a majority to disapprove of the president’s decision should the opportunity arise.

Four Republicans might be enough to join with Senate Democrats and pass legislation rebuking the president, and leadership aides put the number of potential defectors as high as 10. But the unrest seemed well short of the sort of partywide revolt necessary to override a veto by Mr. Trump of any legislative attempt to prevent his declaration of an emergency, leaving a legal challenge as the only recourse.

The GOP Senate is so habituated to walking in lock step with the leadership that most can't imagine doing anything else. This will do great damage to the party unless the strength of the opposition to Der Trumpenfuehrer's junior varsity Enabling Act convinces them their political lives are in serious jeopardy if they don't stand up for our country. Time to let you MoC know what you think.