This explains part of Obama's urgency in seeking a quick passage of the pact. He also knows that other priorities like tax breaks and the budget will soon top the Senate's agenda.

Last Saturday, in his weekly address which usually focuses on domestic issues, Obama focused on the new START treaty instead.

He said everything had been done to meet the demands of the Republican senators, including 18 hearings in the Senate to answer nearly 1,000 questions relating to the pact in the past six months and an extra 4.1 billion U.S. dollars in addition to an existing 80 billion dollars over 10 years for the modernization of the country's nuclear weapons complex.

"Some make no argument against the treaty -- they just ask for more time. But remember this: It has already been 11 months since we've had inspectors in Russia, and every day that goes by without ratification is a day that we lose confidence in our understanding of Russia's nuclear weapons," he told his American audience.

He blamed the partisan climate in Washington last weekend for the delayed ratification of the treaty while he was attending a NATO summit in Lisbon, Portugal. There he won support for the pact from allies.

"My sense is that the discussion is no longer about the terms of the treaty, but about securing funding for modernizing the nuclear weapons conflict, and the Obama administration has been responsive on that," Pifer observed.

"A negotiation is underway between the White House and the Republican leadership," he added. "It is hard to predict whether the Senate will ratify (the treaty) this year; much depends on the Republican leadership."

Republicans have gained much strength in Congress, yet only Obama can sign bills into laws. It is safe to say that there is room for both sides to seek compromise in the days ahead.

Negative consequences for foreign policy

The new START treaty has been touted as a major achievement of the Obama administration in foreign relations and as part of its efforts to reset relations with Russia.

The treaty stipulates that the number of nuclear warheads be reduced to 1,550 on each side over seven years, while the number of delivery vehicles, both deployed and non-deployed, must not exceed 800. It also sets out rules for the verification and monitoring of the nuclear arsenals on both sides.

The pact sets the stage for further arms reductions, as its preamble states that the United States and Russia see the new START as providing fresh impetus to the step-by-step process of reducing and limiting nuclear arms, with a view to expanding this process in the future to a multilateral approach.

"Most people understand that a failure to ratify the treaty would have negative consequences for American foreign policy. Other countries would question U.S. leadership; the reset in relations with Russia would be undercut, which would likely mean less Russian cooperation on key issues such as Iran; and the U.S. ability to secure the support of other countries to raise the bar on nuclear proliferation would be weakened," Pifer said.

But what about the domestic front? "Some might question why Republicans had disregarded the advice of the senior military leadership," he said.