Republicans say they’re trying to create “an environment for private-sector job growth;” Rep. Barney Frank says they’re just trying to stop repeal of Don’t Ask, Don’t Tell.

The evidence for both is the same: A letter to Senate Majority Leader Harry Reid December 1 signed by all 42 Republican senators saying they would not vote to proceed on consideration of “any legislative item until the Senate has acted to fund the government and we have prevented the tax increase….”

Frank says the annual defense authorization bill—which includes language this year to repeal the military’s ban on openly gay servicemembers—is not one of those bills that fund the government, and other controversial bills, such as the DREAM immigration act, are already considered unlikely to pass.

“So, Don’t Ask, Don’t Tell is the only thing that has a real chance to pass,” said Frank, “and this is their way to kill it.”

And Don’t Ask Don’t Tell (DADT) is apparently what they will kill, for there is no alternative parliamentary procedure to get around a vote for cloture—a vote that enables a bill came come to floor despite any senator’s objection. Such votes require 60 votes to succeed, and with 42 Republicans standing firmly against any motion for cloture, no bill can proceed to the floor without at least two Republican turncoats.

Things only get worse next month when the new Congress is seated. Republicans in the 112th Congress will hold 46 seats in the Senate and a majority in the House.

Still, most LGBT groups have not given up—at least not publically. Fred Sainz, a spokesman for the Human Rights Campaign called the Senate Republicans’ letter a “bluff” and said HRC “would expect senators to do the right thing” on the defense authorization bill.

Servicemembers Legal Defense Network urged Reid to try and bring the defense authorization bill to the floor next week anyway.

But Log Cabin Republicans, the national gay Republican group, said it “strongly supports” the Republican letter’s “call to immediately address” the tax issue.

The tax issue is whether Congress will extend tax breaks approved under the Bush administration—tax breaks that are set to expire December 31. Democrats want to extend the cuts only for those making below $250,000; Republicans want to extend them for everybody, including the very rich.

“While time is limited on the legislative calendar,” said R. Clarke Cooper, the organization’s executive director, “the Congress can complete action on taxes as well as a DADT repeal inclusive” defense spending bill.