Richard Lugar is the most knowledgeable senator in either party on arms-control issues. He is pleading with his fellow Republicans to support a treaty, called New START, which would reduce atomic stockpiles while renewing inspections of Russian installations that have lapsed since January.

“Please do your duty for your country,” he said in a message to his colleagues. “We do not have verification of the Russian nuclear posture right now. We’re not going to have it until we sign the START treaty. We’re not going to be able to get rid of further missiles and warheads aimed at us.”

But in today’s Washington, appeals to the national interest over partisan interest make virtually no impact. Not a single Republican has joined Lugar in openly endorsing the treaty and the lead GOP negotiator, Sen. Jon Kyl of Arizona, has said the Senate should not even consider the pact during the current lame-duck session of Congress.

There’s not enough time, insisted Kyl, and the issues are too complex. But that is clearly not true. The Foreign Relations Committee has held 18 hearings on the treaty since it was signed seven months ago and the White House has held more than two-dozen meetings with Kyl or his staff. Obama even met Kyl’s excessive asking price for backing the agreement, $85 billion over 10 years to modernize America’s nuclear arsenal – and Kyl still stiffed them.

Republicans from past administrations are lined up solidly behind the treaty; so has the entire military leadership. As Adm. Mike Mullen, chairman of the Joint Chiefs, told CNN, the treaty would restore “a level of transparency, a level of predictability, a level of certainty with the Russians” that is critical for national security. Can it possibly be true that Henry Kissinger and Mike Mullen have enough information to back the pact but Jon Kyl does not? Of course not.

But the real reason for Kyl’s intransigence is politics, not policy. As the Republican Senate leader Mitch McConnell has said openly and proudly, his main priority is to deny President Obama a second term. That means giving the president no victory, of any kind, at any time. Duty to party trumps duty to country.

Lugar has called out Kyl and his fellow Republicans on this very point. “Sometimes when you prefer not to vote, you attempt to find reasons not to vote,” he told reporters recently.

Treaties require 67 votes for ratification, and when the new Republican senator from Illinois, Mark Kirk, is sworn in next week, Democrats will hold 58 seats. In January, that number will drop to 53, giving Republicans far more leverage. The Republican strategy is clear, Lugar said: avoid “tough choices” now, and hope the treaty dies in the new Senate.

That would be a disaster. The treaty would cut nuclear stockpiles by one-third. Inspection of weapons plants, halted for almost a year, would revive. “There are still thousands of missiles out there,” Lugar warned his fellow Republicans. “You better get that through your heads.”