Did the president have any alternative this time around? Yes.

First of all, he could and should have demanded an increase in the debt ceiling back in December. When asked why he didn’t, he replied that he was sure that Republicans would act responsibly. Great call.

And even now, the Obama administration could have resorted to legal maneuvering to sidestep the debt ceiling, using any of several options. In ordinary circumstances, this might have been an extreme step. But faced with the reality of what is happening, namely raw extortion on the part of a party that, after all, only controls one house of Congress, it would have been totally justifiable.

At the very least, Mr. Obama could have used the possibility of a legal end run to strengthen his bargaining position. Instead, however, he ruled all such options out from the beginning.

But wouldn’t taking a tough stance have worried markets? Probably not. In fact, if I were an investor I would be reassured, not dismayed, by a demonstration that the president is willing and able to stand up to blackmail on the part of right-wing extremists. Instead, he has chosen to demonstrate the opposite.

Make no mistake about it, what we’re witnessing here is a catastrophe on multiple levels.

It is, of course, a political catastrophe for Democrats, who just a few weeks ago seemed to have Republicans on the run over their plan to dismantle Medicare; now Mr. Obama has thrown all that away. And the damage isn’t over: there will be more choke points where Republicans can threaten to create a crisis unless the president surrenders, and they can now act with the confident expectation that he will.

In the long run, however, Democrats won’t be the only losers. What Republicans have just gotten away with calls our whole system of government into question. After all, how can American democracy work if whichever party is most prepared to be ruthless, to threaten the nation’s economic security, gets to dictate policy? And the answer is, maybe it can’t.