President Barack Obama's vision of a world without nuclear weapons earned him a Nobel Peace Prize. But foes are also dismissing the controversial project as naive utopianism or even a threat.

In unveiling his ambitious goal in Prague a year ago, Obama was careful to acknowledge he likely would not see it come to pass in his lifetime.

Russian Deputy Prime Minister Sergei Ivanov echoed those comments this winter. His generation will not see the end of the atomic bomb, he told experts gathered in Munich. But if no efforts are made today, today's grandchildren will not live to see a nuclear weapons-free world either.

There are three chapters to nuclear disarmament, as the world's biggest nuclear power sees it: reducing the military's strategic dependance on nuclear arms, halting proliferation and eliminating these weapons of mass destruction.

The path toward a world without nuclear weapons is a slow, progressive one.

"Improvements in security relations among key states will facilitate arms control and disarmament steps, which in turn beget further improvements in security relations, and so on," explained George Perkovich of the Carnegie Endowment for International Peace.

The steps are sure to be many and filled with treacherous pitfalls detractors are quick to seize upon, leaving supporters struggling to gather steam.

And with the Cold War now fading into memory, the threat of nuclear war is not necessarily topping the long list of international concerns.

"We no longer live in constant fear of a global nuclear war," Secretary of State Hillary Clinton said Friday. But just a day later, she warned that the biggest threat now facing the world was the possibility of nuclear weapons falling into the hands of violent extremist groups like Al-Qaeda.

If nuclear disarmament is back on the agenda today, 42 years after the Nuclear Non-Proliferation Treaty was signed and two decades after the fall of the Iron Curtain, it's also because states like North Korea and Iran risk relaunching the nuclear arms race.

Isolated, these so-called rogue nations pursue their nuclear ambitions while thumbing their nose at international demands and obligations.

The heightened risk is also seized upon by opponents of nuclear disarmament who criticize Obama's steps, including the new START treaty that reduces US and Russian nuclear stockpiles and the revised US nuclear doctrine that limits the use of nuclear weapons.

If the major nuclear powers let down their guard, non-proliferation critics argue, what deterrent will they have left to prevent other countries from using the atomic bomb?

"It's kind of like getting out there on a playground, a bunch of kids, getting ready to fight," conservative darling Sarah Palin said this week in mocking Obama's nuclear disarmament ambitions.

"And one of the kids saying, 'Go ahead, punch me in the face and I'm not going to retaliate. Go ahead and do what you want to with me.'"

Rob Leonard of the Ploughshares Fund acknowledged the nuclear deterrent, but said it was less important than the threat of nuclear weapons proliferating among a growing number of states.

During the Cold War, human error and misunderstandings brought the world not once, but several times on the brink of nuclear war.

"It's reasonable to imagine that accidents and miscalculations could happen with every country that would have weapons and that is destabilizing. If you start to multiply the number of countries, that just increases the risk," Leonard told AFP.

"You don't want to replay the Cold War, because you're not sure it would end up the same way."