During the most heated parts of the Cold War, America’s huge arsenal of long-range nuclear weapons clearly served their intended purpose. Mutually assured destruction — the fact that so many weapons were deployed, neither the United States nor the Soviet Union could assure its survival once the bombs flew — arguably prevented world ruin.

But the Soviet Union is gone, and with it the need to maintain massive nuclear arsenals. That’s been the premise behind both the START I treaty — agreed to by both Washington and Moscow in 1991 — and START II, which was approved by the U.S. Senate in 1996 but still stalled in the Russian Duma.

To its partial credit, the Clinton administration has intended to follow the guidelines of the START II treaty, which will reduce today’s 6,000-warhead cap to between 3,000 and 3,500 warheads. And the U.S. has also taken the moral lead in pushing other nations, such as North Korea, India, Pakistan, China and Russia to halt or severely scale back their nuclear-testing programs.

But activists rightly note the flaw in Washington’s policy: The U.S. Energy Department plans to refurbish half of our nuclear warheads, and put them into storage. The policy, called lead and hedge, has America take the lead in pushing for arms reduction, but preparing to ramp up missile deployments if another nation begins a swift build-up.

The flaw in that policy is assuming the old Cold War rules apply to today’s nuclear threats when it does not. Mutually assured destruction pitted two clear enemies in a contest to effectively prevent the other from having superiority, and to make nuclear war ultimately futile.

MAD assumed those two adversaries would make logical choices; fortunately, that’s how it worked out. But the rogue states that are developing nuclear weapons today have different aims than asserting a dominating ideology — their aims may be shorter term, more difuse and less clearly spelled out. The riddle of North Korea serves as an example.

U.S. policy needs to focus on restricting the development of new nuclear weapons and impeding the ability of new nuclear powers from being able to deploy those weapons. Engaging in arms races with madmen won’t make us more secure; it will only encourage the madmen to act sooner.

The Clinton administration should honor the START II missile levels, and forget about storing weapons of mass destruction.