by DAVID AXE

Two years ago, the U.S. and Russia signed a new treaty meant to reduce both countries’ nuclear arsenals—an historic move signalling the continuing relaxing of decades-old tensions between the two powers.

But in surprising and temporary development, America has actually increased its atomic holdings in the past six months. Russia, by contrast, shed nukes over the same period.

That disparity, however fleeting, is a big problem.

Formally known as “Measures for the Further Reduction and Limitation of Strategic Offensive Arms”—or “New START,” for short—the treaty is supposed to see America and Russia reduce their atomic arms to no more than 1,550 warheads apiece on 700 deployed launchers by 2018.

In 2011 the U.S. possessed around 1,800 nukes and 900 launchers including missiles launched from ground silos, submarines and bombers. At the same time, Russia had approximately 1,700 warheads on 500 launch vehicles.

To get to the new, lower warhead total required by the treaty, Moscow has been steadily cutting weapons. The Russians had 1,400 nukes on 473 launchers on Sept. 1, according to the latest data provided by the U.S. State Department. But following a period of slow cuts the Pentagon actually added 34 warheads and 17 launchers in the past half-year, for a total of 1,688 warheads and 809 launchers on Sept. 1.

The Americans’ atomic increase “probably reflects fluctuations mainly in the number of missiles on-board ballistic missile submarines at the time of the count,” writes Hans Kristensen, an expert on nuclear weapons with the Federation of American Scientists. The U.S. still expects to meet the treaty’s 2018 deadline for fewer nukes.

But that doesn’t mean there isn’t a problem in these numbers. Moscow is rushing to shrink its potentially world-destroying arsenal even beyond the treaty’s requirements, but Washington isn’t doing the same with its own atomic stockpile. That’s evident from continuing U.S. investment in key nuclear technologies such as the tritium rods that trigger atomic explosions.

“Russia is already 227 deployed missiles and bombers below the 700 limit established by the treaty for 2018, and might well drop by another 40 by then to about 430 deployed strategic launchers,” Kristensen writes. “The United States plans to keep the full 700 launchers.”

That gap could destabilize relations between the two countries, Kristensen warns. “The disparity can complicate arms reductions and be used to justify retaining excessively large expensive nuclear force structures.” In other words, if the Russians sense the Americans are dragging their feet on disarmament, they might just decide to reverse the process and rearm.

Better for Washington to match Moscow’s voluntary and speedy nuke cuts. But tell that to Republicans in the U.S. Congress. They, more than the administration of Pres. Barack Obama, are opposed to U.S. atomic cuts, however self-defeating that recalcitrance might be.

“In a truly bizarre twist, U.S. lawmakers and others opposing additional nuclear reductions by the Obama administration could end up help providing the excuse for the very Russia nuclear modernization they warn against,” Kristensen writes.

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