For years, Christian conservatives have backed the GOP for a kiss and a promise. They usually end up with a kiss-off. But that screeching noise from under the GOP’s big tent this year is the sound the religious right makes when it tired of turning the other cheek.

In a warning as clear as the Ten Commandments, some of President Bush’s most ardent supporters have told him to move the anti-gay marriage amendment closer to the top of his domestic agenda or they will withdraw their support for his Social Security reform.

Leading the charge is the Arlington Group, a newly formed coalition of religious leaders who backed the president, in part, because he claimed he’d fight for the ban.

But Bush didn’t even mention it in his inaugural address, nor was it listed in a 10-point legislative agenda Republican congressional leaders unveiled this week.

The Rev. James Dobson of Focus on the Family, one of the leaders of the Arlington Group, took one look at the GOP agenda and ordered an immediate revision.

“If Republicans,” Dobson said in an interview on the Focus on the Family Web site, “do what they’ve done in the past, which is say `thanks so much for putting us in power; now we don’t want to talk to you anymore,’ they will pay a serious price in four or maybe two years.”

That’s pretty tough talk. Considering the clout they brought to this last presidential election, you’d think they were in a position to demand what they want.

You’d be wrong. The president hardly lifted a finger to fight for an anti-gay-marriage amendment to the U.S. Constitution in his first four years. He may actually lift a finger this time. But he won’t get it done.

Nor will conservatives make much headway in the fight to alter Roe v. Wade. Abortion foes who helped elect them last year are getting the same old lip service they get after each election.

The crowd who showed up on the National Mall in the annual March for Life on Monday got a canned speech from the president’s retreat in Camp David. No Republican president in 25 years has shown up for the march.

“The America of our dreams where every child is welcomed in law. …” Bush said, “may still be some ways away.”

He pointed out the ban on partial-birth abortions passed last year. But conservatives know that law won’t even make a dent in the more-than-a-million legal abortions a year performed since Roe v. Wade.

It’s going to take a lot more to appease the Arlington Group.

In a letter to Karl Rove a week ago, they criticized Bush’s “defeatist attitude on an issue that is at the top of our agenda.”

If Bush is “reluctant to devote the same energy to preserving traditional marriage,” the letter said, it would “create outrage with countless voters who stood with him a few weeks ago.”

That would be the same kind of outrage black voters and labor leaders have felt when the Democratic Party has abandoned their agendas for a more moderate path.

They fire off nasty confidential letters, which they later leak to the press. They threaten mass defections.

But in the end, they are left to choose between the gradualism of their own party and the total disregard of the other party. Welcome to the big tent.