THE REPUBLICAN PARTY platform includes some scare talk. “The United States is the only nuclear power not modernizing its nuclear stockpile,” the platform warns. “It took the current administration just one year to renege on the President’s commitment to modernize the neglected infrastructure of the nuclear weapons complex — a commitment made in exchange for approval of the New Start treaty.”

These statements are wrong and misleading. President Obama has increased the budget for nuclear weapons and the weapons complex. The president doesn’t like to talk about it as much — he prefers the lofty speech about a world free of nuclear weapons — but the truth is that in this realm he’s a big spender.

On the nuclear stockpile, the National Nuclear Security Administration, a part of the Energy Department, is undertaking a 20-year, multi­billion-dollar effort, known as the Life Extension Programs, to prolong the life of four types of nuclear warheads and bombs. Just one of them, the B-61 gravity bomb, is facing enormous new cost estimates. While the president has said he won’t build new nuclear weapons, the existing arsenal is getting a massive and costly overhaul.

More broadly, the United States is modernizing the triad: the land-sea-air combination of planes, submarines and missiles that delivers the nuclear bombs and warheads. While some have suggested it may be overkill two decades after the Cold War ended, the president decided to keep the triad intact. The modernization of the Minuteman III intercontinental ballistic missile and the Trident II submarine-launched ballistic missile is underway, and the Navy is planning to replace the Ohio-class ballistic missile submarines. Not a sign of weakness there.

Congressional Republicans have been griping lately that Mr. Obama broke faith with a 10-year spending projection for nuclear weapons activities laid out when the New Start treaty was submitted for Senate ratification in 2010. In fact, led by House Republicans, Congress last year cut back the president’s proposed spending for nuclear weapons. Mr. Obama’s proposed 2013 budget is just slightly below the original top line of the 10-year plan — $7.58 billion, compared with $7.95 billion — because of the congressional cuts and the growing pressure on spending. This minor dip is not bad faith, “reneging” or unilateral disarmament; rather, it is how Congress and government work. Mr. Obama’s nuclear weapons budgets are still sizably above those left by President George W. Bush.

The president made a commitment in a letter to the Senate in February 2011 to accelerate, “to the extent possible,” the design and engineering of a new plutonium facility, the Chemical and Metallurgy Research Replacement building at the Los Alamos National Laboratory in New Mexico. But after escalating costs and budget cuts by Congress, the administration decided that it could not sustain this project and another multibillion-dollar uranium plant in Tennessee. So the president made choices and proposed in his 2013 budget to defer work on the plutonium facility for five years. Again, a reasonable response to changing ­circumstances.

It is wrong for Republicans to turn these fiscal hiccups into campaign broadsides. The United States has the most accurate, powerful and modern nuclear force in the world. Unfortunately, too much of the nuclear weapons argument is still trapped in a Cold War mind-set, as if the Soviet Union were still around. What we need now is a thorough going debate on the role of nuclear deterrence in the 21st century and what arsenal will most properly and effectively meet the ­challenge.