President Obama's nuclear-weapons policy is finally taking shape. We now have the text of his "New START" treaty with Russia, the Nuclear Posture Review (NPR) and statements on fissile materials at the Nuclear Security Summit in Washington.

But as the policy picture comes into focus, most of what we see is troubling.

For starters, there is this irritating habit of wanting moral credit for wishful thinking. Mr. Obama has said his ultimate goal is "a world without nuclear weapons." Nobody seriously believes this will happen, yet his administration solemnly links the treaty and the otherwise dour and serious NPR to this airy goal. With a wink and nod, they seem to think the masses (especially their supporters) will believe the hype, even though the experts know something very different.

What the experts hope is that the new START treaty and the NPR will reduce the world's reliance on nuclear weapons. But that laudable hope may be groundless, too.

The administration says our greatest threats are Iran and terrorist acquisition of nuclear weapons — not Russia. Yet, the new treaty will do nothing to convince Iran or other rogue states and terrorists to follow our disarmament lead. Not only that, it increases the centrality of nuclear weapons in the U.S.-Russian strategic balance, playing right into Russia's desire to be our "peer" competitor based largely on nuclear weapons.

The biggest problem with the new treaty is how lopsided it is in Russia's favor. Because of financial constraints and outdated nuclear systems, Russias nuclear arsenal was already going down, especially its aging launchers and delivery systems. It would have likely been forced to make the reductions codified in this treaty whether or not the U.S. reduced its weapons.

And yet if the treaty is ratified, we will have locked ourselves into reductions that cannot be changed. Were we ever to want to increase our nuclear arsenal — say, because China or some other country threatens us — doing so would put ourselves in violation of international law.

The new START also will give better protection to Russians than Americans. Once it is fully in force, we have to cut 151 of our delivery vehicles and launchers, while Russia could actually add 134 and still be under the limit of 700. The only side that's disarming on this score, then, will be the U.S.

Yes, the Russians may have to cut 190 nuclear warheads; but even there, we are disadvantaged; we could have to cut 265 to get to the treaty's limit of 1,550 (though warhead accounting rules for bombers make the actual numbers uncertain).

This is not only unfair. It actually lessens Russia's exposure to America's nuclear weapons more than it reduces America's exposure to Russia's weapons.

Who cares, you ask, since we know that our biggest threat is not from Russians, but from Iranians? Well, if that is so, then why are we making such a big deal of an arms agreement with the Russians as if the Cold War had never ended? Why are we constraining our nuclear options in other areas just to get this modest reduction from a country that the administration otherwise seems to believe is a "reset" strategic partner?

On top of this, the START treaty includes language that Russia says it will use to limit our missile defenses. Nor will the treaty limit Russia's huge arsenal of tactical nuclear weapons. So you can see how the goal of protecting Americans from real weapons — as opposed to the goal of reducing some vague global threat — gets short shrift.

Perhaps the biggest long-term flaw in both this new treaty and the Nuclear Posture Review is that there is only an uncertain commitment to further nuclear modernization. Sens. John McCain and Jon Kyl called the Obama administration on this point in an April 8 statement, warning, "[W]e continue to believe it will be difficult for it [the new START treaty] to pass the Senate without the fully funded robust nuclear weapons modernization program required by section 1251 of the National Defense Authorization Act of 2010."

This concern is more than just about modernizing and testing new weapons to deter conflict. It's about obeying the law. The president must submit a modernization plan when he sends the treaty to the Senate for consideration. We can judge then whether it meets the bill.

It is certainly not a bad thing to reduce our reliance on nuclear weapons if we maintain the right force balance — with active missile defenses and the right conventional forces — and make a clear distinction between nations that favor liberty and those that favor aggression.

It is simply wrong to blithely assert that just reducing nuclear weapons (especially when we are doing most of the cutting) is good for America and world peace.

• Kim R. Holmes, a former assistant secretary of state, is a vice president at the Heritage Foundation.