http://www.washingtonmonthly.com/archives/individual/2009_05/018151.php"Obama's new budget plan includes a little-noted sea change in U.S. nuclear policy, and a step towards his vision of a denuclearized world. It provides no funding for the Reliable Replacement Warhead program, created to design a new generation of long-lasting nuclear weapons that don't need to be tested. (The military is worried that a nuclear test moratorium in effect since 1992 might endanger the reliability of an aging US arsenal.) But this spring Obama issued a bold call for a world free of nuclear weapons, and part of that vision entails leading by example. That means halting programs that expand the American nuclear stockpile. For the past two budget years the Democratic Congress has refused to fund the Bush-era program. But Obama's budget kills the National Nuclear Security Administration program once and for all.
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The idea behind US agreements with the Soviet Union to stop testing and stop building more nuclear weapons was to let the stockpiles age and become less reliable so that we'd be less likely to blow up the world.
The Bush Administration acted like it was a crisis that our nuclear stockpile was aging, when that was the point of those agreements.