So the big housing bill has passed Congress. That’s good news: Fannie and Freddie had to be rescued, and the bill’s other main provision — a special loan program to head off foreclosures — will help some hard-pressed families. It’s much better to have this bill than not.

But I hope nobody thinks that Congress has done all, or even a large fraction, of what needs to be done.

This bill is the latest in a series of temporary fixes to the financial system — attempts to hold the thing together with bungee cords and masking tape — that have, at least so far, succeeded in staving off complete collapse. But those fixes have done nothing to resolve the system’s underlying flaws. In fact, they set the stage for even bigger future disasters — unless they’re followed up with fundamental reforms.

Before I get to that, let’s be clear about one thing: Even if this bill succeeds in its aims, …