Columnist

Be wary of anyone who purports to understand the deep meaning of President Trump's decision to side with the Democrats on short-term budget issues. Nobody knows what he's up to, and this probably includes Trump himself.

Nonetheless, his recent foray into bipartisanship provides the occasion to explore the path he chose not to take at the beginning of his administration. He had the opportunity to put Democrats in a tight spot. Instead, he has spent his energies since Jan. 20 strengthening the hand of his opponents and weakening his own party.

If Trump had opened his presidency by detailing a major infrastructure plan, Senate Minority Leader Charles E. Schumer (D-N.Y.) and his colleagues would have had no choice but to cooperate, as Schumer himself signaled at the time. If Trump had also lived up to the promises of his campaign by proposing to make Obamacare better and not simply pushing for repeal, he might have fostered a similar spirit of bipartisan engagement.

He could have linked these ­Democratic-friendly ideas with an early call for tax cuts as part of tax reform, which would have made Republicans happy, as has his ongoing work to eviscerate Obama-era business regulations.

All this might have added to the deficit in a big way, but Trump has always lived on debt. This course would have been seen by some critics as philosophically muddled and by some conservatives as betrayal. But you can imagine that the prevailing wisdom in Washington would have praised him for breaking through "stale" political categories and "rising above" the old partisan fights. He could also have given himself more bargaining room by putting everyone, Democrats as well as Republicans, in play.

It could be that Trump's latest move is a reach for this lost chance, although it seemed to be more impulse than strategy. It was also sudden. No one on either side was prepared for Trump's embrace of Schumer and House Minority Leader Nancy Pelosi's (D-Calif.) suggestion to pass hurricane relief now and to set up December as the time for serious haggling. Democrats are likely to have more leverage then.

Being who he is, Trump might have wanted to take a slap at his putative allies, Senate Majority Leader Mitch McConnell (R-Ky.) and House Speaker Paul D. Ryan (R-Wis.), both of whom he seems to dislike intensely. And perhaps he was looking for a few days of good headlines. Pelosi reported he reveled in the great media coverage he received, as good an indicator as any that this is a guy who operates day to day.

Trump's problem with moving from a relatively small policy gesture to an entirely new approach is that the immediate past cannot be erased.

He is a far weaker figure today than he was when he was inaugurated. His poll numbers are terrible, the Russia story has ballooned in importance, and Democrats are in no mood to throw him any lifelines. His words and actions on race and deportations have erected new moral barriers to any pragmatic turn toward working with him. "All he's done in eight months," said a senior Senate Democratic aide, "is make the price of cooperation a lot higher."

In the meantime, he has filled his Cabinet largely with conservative loyalists, further complicating any triangulation strategy involving Democrats. One member of his inner circle who might be best positioned to work with Democrats, Gary Cohn, his senior economic adviser, is apparently so on the outs that there are reports he may soon be gone. Trump might have run against GOP orthodoxy in the primaries, but so much of what he has done so far would have been in any right-wing Republican's playbook.

He is still somewhat distinctive in his nativism, but this hardly bodes well for cooperation with progressives and moderates. And oddly enough, the departure of nationalist-in-chief Stephen K. Bannon removed one voice in his circle advocating positions on infrastructure, trade and taxes that had at least something in common with Democratic views.

Democrats will certainly try to press the temporary advantage they seem to have on behalf of immigrants endangered by Trump's moves against the Deferred Action for Childhood Arrivals program. They'll also push for Obamacare funding, an end to the debt ceiling and a variety of budget concessions.

We should have learned long ago that looking for coherence from this president is a fool's errand. He may have happened on a wiser political strategy too late to do himself much good but just in time to hurt his already ailing party even more.

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