One problem I have in addressing these matters is that I was a late "convert" to the fullness of the Church's teaching in regards to just war theory, the incalculable evil of our use of nuclear weapons in World War II, and similar matters. I tended to dismiss serious concerns about these things as mere Catholic liberalism, which to me was identified with liturgical laxity, indifference to Church teaching about sexual morality, and the like.
It took reading some books and watching some movies about the devastation our use of nuclear weapons caused at Hiroshima and Nagasaki, and going from there to explore the ideas the Church had developed about the parameters of a just war, before I realized that my positions on these issues were not at all in harmony with the Catholic faith. But because I came to this realization rather late, I have not done the amount of study necessary to be able to discuss these issues with good clarity.
Take, for instance, the recent news reports about President Obama's intention to enter a nuclear disarmament treaty with Russian President Dmitry Medvedev. On the one hand, since the scenarios where it would ever be permissible, morally, to deploy a nuclear weapon are few if they even exist at all, it seems like having fewer of these frighteningly destructive weapons around would be a good thing.
But on the other hand, I'm quite sympathetic to the logic and reason of an opinion piece like this one:
Is there any proper defensive reason to maintain a large nuclear arsenal? Is the creation of pacts and treaties just window-dressing, ignoring that the threat of a rogue nation's nuclear attack might be greater than any threat of a nuclear strike between larger countries? If Catholics think that we would likely be acting immorally to deploy nuclear weapons even defensively, is there any justification in retaining a large and aging arsenal of these weapons? Does the fact that the technology exists and is widespread and unlikely to disappear change the moral considerations at all, as concerns disarmament?
A second lesson is that the NPT invites multiple opportunities to cheat by insisting that all states, including those suspected of violations, have a "right" to civilian nuclear technology.
As Henry Sokolski of the Nonproliferation Policy Education Center reminds us, "so long as there is some conceivable civilian application [for a nuclear technology], and the offending activity or material is admitted to or declared to international inspectors, the international community ultimately presumes what it senses to be suspect must be treated as if it was peaceful and legitimate and, therefore, unactionable." This is one lesson of the Atoms for Peace folly of the 1950s.
To the extent that more states haven't gone nuclear, the reason has been U.S. power, not a treaty. Japan, Taiwan, South Korea and Canada could build a bomb in a week, but instead they have long relied on America's nuclear umbrella to deter aggressors. A credible U.S. nuclear deterrent is the world's greatest antiproliferation weapon.
As for New Start, its most striking trait is its Cold War mentality. The pact emphasizes the relative size of the U.S and Russian arsenals, as if a nuclear exchange between these two countries is the world's greatest current threat. The treaty is thus of little strategic consequence, though the Senate should ask why its ceiling on 800 U.S. launchers (many of which now carry conventional payloads) is below the 860 that the Pentagon prefers.
I have heard some Catholics say that disarmament, including unilateral disarmament, is the only morally correct approach to nuclear weapons. I would really like to hear from those better equipped to discuss the moral theology than I am as to whether that is true or not.