Washington (CNN) Donald Trump may not realize it totally yet, but yesterday was the last easy-ish day of his presidency.

By noon (or so) Thursday, Nancy Pelosi will become the new speaker of the House of Representatives -- formalizing the Democratic majority her side won in last November's election. And that will change everything.

Trump has sought to look on the bright side of divided control of government to date -- insisting that maybe he will be able to make deals with the new Democratic majority in the House. "It really could be a beautiful bipartisan situation," he said at a press conference the day after the 2018 election.

But the early returns are not promising. The federal government has been shut down for the past 12 days -- and there's little reason to believe that will change at any point soon. Trump has dug in on his demand for $5 billion to fund construction of his border wall. Pelosi and Senate Minority Leader Chuck Schumer, of New York, are equally dead-set on providing zero dollars for Trump's wall.

And this is only the beginning. Starting today, Democrats in the House will make Trump's life a living hell. Efforts are already underway to bring a number of his Cabinet officials before Congress, to extricate his tax returns from his grip and to more deeply probe his business dealings both before and during his presidency.

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