President Obama's pledge to seek a world without nuclear weapons - reiterated in a speech last month in Prague - represents one of the most critical elements of his national security agenda. Nuclear weapons serve no military purpose, and the use of even one of these instruments of mass terror would cause unparalleled destruction. But that hasn't stopped a chorus of neo-conservative critics - the same folks who pushed for war with Iraq based on false claims regarding its alleged weapons of mass destruction -- from dismissing Obama's anti-nuclear agenda as "naïve," and "unrealistic."

Two recent anti-arms control critiques - one by former George W. Bush and Donald Rumsfeld speech writer Marc Thiessen and one by right-wing think tanker Frank Gaffney - are representative of the neo-conservative case for a world filled with nuclear weapons. Given that both of these men supported the invasion of Iraq based on claims of Saddam Hussein's possession of nuclear, chemical and biological weapons - weapons that proved to be nonexistent - their credibility to speak on nuclear issues is seriously compromised, to put it mildly. But speak they will, in any and every forum available to them, so it's worth taking a look at some of their main arguments.

First, in a self-published piece on "Obama's Unreal Nuclear Agenda," Frank Gaffney - the man who never met an arms control agreement he could support, including those signed by his former boss Ronald Reagan - cites one primary objection to Obama's pledge to pursue the elimination of nuclear weapons: that it's impossible to keep other countries from secretly developing their own nuclear bombs.

Gaffney's claim may sound vaguely plausible, but upon further scrutiny, his argument falls apart. Developing and fielding a nuclear weapon is a difficult thing to do. It involves major industrial and research capabilities that cannot be hidden indefinitely. And under a regime of rigorous inspections the prospects of hiding such a weapon are near zero. Assuming an U.S. adversary were somehow to get hold of one or two bombs, they would be suicidal to use them against the United States or its close allies. Perhaps most importantly, an arms control agreement like the Comprehensive Test Ban Treaty would make it far less likely that any new nations could get nuclear weapons, while Gaffney's vision of a "treaty-free world" would make nuclear proliferation far more likely.

Second, in a Wall Street Journal piece entitled "The Arms Control Dinosaurs Are Back," Thiessen asserts that detailed arms control agreements are too cumbersome and too unreliable to meet U.S. security needs. Instead, he promotes voluntary reductions of the sort embarked upon by the Bush administration as part of the 2002 Moscow Treaty. Essentially what Thiessen seems to be saying is that he is against treaties, unless they are as loose and unenforceable as the three-page agreement Bush entered into with Vladimir Putin - a treaty with no verification procedures and no requirement to make nuclear reductions permanent. In fact, after 2012, the Bush-Putin accord lapses and Washingon and Moscow can do whatever they want to with their nuclear arsenals. By contrast, a follow- on to the Strategic Arms Reduction Treaty would lock in reductions through a strict verification regime. These permanent reductions would in turn be the best building blocks for further arrangements aimed at eliminating global nuclear arsenals.

In assuming that we can somehow live with a world filled with nuclear weapons without even attempting to do anything to get rid of them it is the neo-conservatives who are naïve. Their only apparent solution -- bombing or threatening to bomb countries that appear to be seeking nuclear weapons -- would make matters much worse, while killing tens or even hundreds of people in the process.