Nuclear weapons are already disappearing, and elaborate international plans like the one Obama is pushing aren't needed to make it happen. During the Cold War, painstakingly negotiated treaties did little to advance the cause of disarmament -- and some efforts, such as the 1972 SALT Agreement, made the situation worse from a military standpoint. With the easing of tensions after the Cold War, a sort of negative arms race has taken place, and the weapons have been going away more or less by themselves as policymakers wake up to the fact that having fewer useless things is cheaper than having more of them. By 2002, the number of deployed warheads in Russian and U.S. arsenals had dropped from 70,000 to around 30,000, and it now stands at less than 10,000. "Real arms control," wistfully reflected former U.S. assistant secretary of state for arms control Avis Bohlen in an essay last May, "became possible only when it was no longer necessary."
In his 2008 campaign, Obama pointedly pledged that, as president, he would "do everything in my power to prevent Iran from obtaining a nuclear weapon … everything." Let us hope not: The anti-proliferation sanctions imposed on Iraq in the 1990s probably led to more deaths than the bombs dropped on Hiroshima and Nagasaki, and the same can be said for the ongoing war in Iraq, sold as an effort to root out Saddam Hussein's nukes. There is nothing inherently wrong with making nonproliferation a high priority, so long as it is topped with a somewhat higher one: avoiding policies that can lead to the deaths of tens or hundreds of thousands of people under the obsessive sway of worst-case-scenario fantasies.
The whole article is well worth reading. A mature, sober, (one might say "realist") look at nuclear weapons policy in this day and age.