When I heard Saturday morning that the president was going to give a Rose Garden address that afternoon, I assumed he’d announce he had made up his mind to bomb Syria. And he did announce that—but he’s going to ask Congress for permission first. He’s chosen the occasion of a war that over 50 percent of Americans oppose to teach a civics lesson. It’s perhaps the best thing he’s done as president.

“This could be the biggest miscalculation of his presidency,” is what a “a senior House Democrat” tells Politico. I suspect Obama has a pretty good count on how Congress will vote, but nobody thinks it’s absolutely a forgone conclusion that he’ll get his war. (There’s maybe a 10 percent chance he won’t get it—not great odds for the cause of peace, but a lot better than what they’d be if Obama acted alone.)

Obama insists that he doesn’t strictly need congressional authorization. The problem with that is threefold:

1.) It doesn’t square with what Obama told the Boston Globe in 2008—”The president does not have power under the Constitution to unilaterally authorize a military attack in a situation that does not involve stopping an actual or imminent threat to the nation”—or with what then-Sen. Joe Biden said a year earlier about the prospect of Bush attacking Iran: “if he takes this nation to war in Iran, without congressional approval—I will make it my business to impeach him.”

2.) Politically, it’s to Obama’s advantage to have the Republicans in Congress as exposed as he is if the war metastasizes—though I suspect the cover he’ll get from having Boehner or McCain with him won’t help a Democrat in 2016 facing someone like Rand Paul.

3.) Less cynically, and even apart from the legal and constitutional issues, war requires a degree of national resolve beyond what the executive branch alone can supply. If Obama and his allies in Congress can’t get the votes, that will be an deafeningly clear signal to the president just what dangers other Americans perceive in this operation.

Obama hasn’t always seemed comfortable wielding executive power—he didn’t have any experience with it when he came to the Oval Office, and as his 2008 remarks recall, he first established himself as a national figure in opposition to the way George W. Bush had handled the office. That opposition was never as deep as his admirers liked to think, but if the pre-presidential Obama wasn’t entirely a facade, there’s perhaps still a trace of that personality lurking in the commander in chief’s skull. Enough of a trace that he prefers to teach his own version of a constitutional-law lesson—his own version, I stress, with his reservation that asking Congress is just polite, not required—rather than take the path of least resistance to starting the war he wants to wage.

Allowing even the slightest theoretical possibility that the president may not have unilateral power to wage war anywhere, any time, for any reason has already disturbed Bill Kristol, who in a Weekly Standard blog post oh-so-unironically titled “Congressional Republicans: Hail Ceasar!” quotes UVA’s James Ceasar—a Straussian with the penchant for executive authority characteristic of many of that breed—telling Republicans to vote for Obama’s war

even if they think that the President’s policy will prove ineffective, do no good, waste money, or entail unforeseen risks; they should do so even if they think he has gotten the nation into this situation by blunders, fecklessness, arrogance, or naiveté; and they should so even if, and especially, if they have no confidence in his judgment. The simple fact is that the nation and our allies will be at further risk if the world sees a presidency that is weakened and that has no credibility to act.

“Further at risk” of what, O Ceasar? The president’s power to respond to immediate threats isn’t at stake here, only his power to launch a war of choice on a collapsing state that poses no threat to the United States. I wish Kristol and his gang would offer a civics lesson as clear as Obama’s—let them campaign for outright martial law and the removal of any check on the president’s power to commit Americans to killing and dying overseas. Until that’s the law, though, it seems like these are questions that ought to be debated by Congress and the people.

Legislators ought to take the president’s request in this instance as an opportunity to teach a lesson of their own, namely that Article I, Section 8, Clause 11 of the U.S. Constitution is still in force, and when Congress says “no” that means “no.”