This isn't as surprising as The Washington Post thinks:
An unusual split has opened between conservative Republicans and the American military leadership over the U.S.-Russia nuclear treaty, with current and former generals urging swift passage but politicians expressing far more skepticism. [...]
But five Republicans on the Senate Foreign Relations Committee said in a recent report that New START was "a bad deal." They added that U.S. military leaders had made assumptions about the pact -- including that Russia will honor it -- that are "optimistic in the extreme."
Meanwhile, the conservative Heritage Foundation's grass-roots lobbying arm is targeting Republican senators with mailings warning that the treaty "benefits Russia's interests, not ours."
As a rule, conservatives are completely supportive of military leaders, except when those military leaders disagree with conservatives. Now, this isn't much of a problem; we wouldn't actually want a political movement that took it's marching orders from the military. Still, for a political movement that claims exclusive domain over "supporting the troops," it's pretty hypocritical.
One other thing; after thinking a little more about conservative opposition to the new START treaty, I've come to the conclusion that it isn't entirely political. Generally speaking, conservatives view the world in starkly zero-sum terms: if poor people make gains, then rich people must suffer, if minorities get benefits, then white people must lose theirs, and if Russia gains (or China, or Europe, etc.), then America must lose. You see this in the comment from Heritage that "the treaty benefits Russia's interests, not ours." That international relations (along with everything else) are fundamentally zero-sum is a core part of conservative ideology and goes a long way toward explaining their opposition to diplomacy and anything that doesn't involve needless belligerence and long, costly wars.
-- Jamelle Bouie