The "takings" clause of the Fifth Amendment is for conservatives what the equal protection clause of the 14th is for liberals. It wouldn't be fair to say that conservatives cherish property the way liberals cherish equality. But it would be fair to say that the takings clause is the conservatives' recipe for judicial activism -- imposing their agenda through the courts rather than bothering with democracy -- just as they say liberals have misused the equal protection clause.

Of course, conservatives always claim to be against judicial activism. Liberals have long suspected that this was a decoy and that once conservatives had control of the federal courts they would twist their mustaches, laugh contemptuously and reveal the various policies they planned to impose by judicial fiat. Conservatives and liberals alike have been waiting for this moment for a third of a century. Each Supreme Court appointment by a Republican president seems to be "it." And yet "it" hasn't happened. Roe v. Wade -- the high-water mark of liberal judicial activism -- still stands. And on Thursday the court said a surprising "no thanks" to judicial activism, Republican style.

The equal protection clause was a handy tool because just about anything the government does or doesn't do can be framed as treating people unequally. You get pulled over for speeding, and he doesn't; she gets a job, and you don't; the president calls on him at a news conference and not you, and so on. When does unequal treatment become unconstitutional? In the heyday of the Warren Court, almost anything on your wish list was at least worth a try.

Almost any government activity can also be seen as taking property "without just compensation." The basic model of an unconstitutional "taking" would be if the government threw you out of your house. But Richard Epstein, a University of Chicago Law School professor and the godfather of the "takings" movement, says: Okay, what if you owned two houses and the government took one of them. Still a taking. So suppose that the government took a half-interest in both houses? What's the difference? Or what if the government enacts zoning or environmental regulations that reduce the value of your house by half? Or gives someone a government benefit that you don't get, but, as a taxpayer, will have to pay for?

In law school, this is called "salami slicing" and it has been known to drive people mad, including, in the opinion of some, Professor Epstein. But his logic is compelling. Once you start down the takings road, it's hard to stop before Epsteinville. Possibly for that reason, the Supreme Court has clung pretty tightly to literalism and declined repeated invitations to use the takings clause like a scythe to cut the government down to size.

The case decided on Thursday, though, seemed promising to takings fans because it wasn't about compensation. It was about the requirement that any government taking must have a "public purpose." They can't take your house and give it to the mayor's mistress, even if they pay you for it. But they can, apparently, take your house and tear it down to make room for a development of trendy shops and restaurants, a hotel and so on. That was the plan in New London, Conn., until a few working-class spoilsports wouldn't budge.

The court ruled, 5 to 4, that yuppification is a valid public purpose. Or at least it was reasonable for the city to promote yuppification. Who wouldn't like a few more Starbuckses in town? The four dissenters (O'Connor, Scalia, Thomas and the Chief) said: If this is a "public purpose," what in the world is not?

One answer is that the town's elected officials thought that the project served a public purpose and that the various subsidies and favors were worth the price. But they may or may not have thought this. When the local government showers a big development with money and favors, it's usually not about sovereignty but about lack of sovereignty. Private developers play jurisdictions off against one another, extracting concessions from all that none would actually make a sovereign decision to give. A Supreme Court decision that concessions of this sort were unconstitutional would have taken them off the table and actually increased the effective sovereignty of elected officials.

A couple of weeks ago, the court ruled that states cannot exempt themselves from federal laws against the medical use of marijuana. Although in a narrow sense this was a victory for a conservative policy, in a wider sense it also closed off an avenue for conservative activism. Like almost all assertions of federal power over the states, this one was based on the Constitution's commerce clause. The logic is often far-fetched -- how does medical marijuana affect interstate commerce? -- and some conservatives would like judges to start throwing out federal laws wholesale on commerce clause grounds. The court once again said no thanks.

So the danger of conservative judicial activism has been averted for another year. Stay tuned.

The writer is editorial and opinion editor of the Los Angeles Times.