Could Trump build a wall all by himself, or might he need Congress’s approval? Could Trump deport a million illegal immigrants all by himself, or might he need Congress’s approval? Is there, really, anything Trump could do all by himself, without Congress’s approval? Is there anything he could do that would not be subject to being undone, or prohibited, by Congress?

The answer is twofold. First, Trump would clearly have some power to act unilaterally by executive order — and Democrats, having for seven years cheered on the extravagant use of that power, are understandably apoplectic as they contemplate Trump using the same tool. (We will now pause for five minutes of smirking.)

Second, whatever the president does, Congress, if it has the will, can amend or undo. With a lot of empathetic Democrats in Congress, Republicans, whether constituting a majority or not, should have little trouble managing a President Trump.

The point is this: If Congress ceases to be an actively functioning political institution, political liberty in the United States will come to an end. All Americans, and especially conservatives, need to understand that if a Trump presidency is a constitutional or military disaster (to be distinguished from a disappointment), the real fault will lie, not with President Trump, but with Congress, which holds the high card and will need to remind Trump of that every day: unlike Annie’s tomorrow, always a day away, impeachment can be voted on today.