Are some US nuclear weapons so old and finicky they need to be rebuilt into simpler, sturdier bombs?
Should scientists at the nation's nuclear labs study new kinds of weapons specifically intended to frighten rogue dictators?
Right now the US is observing a moratorium on nuclear tests. Should it spend a little cash and improve the readiness level of the Nevada Nuclear Test Site - just in case?
As Washington worries about possible proliferation in Iran and North Korea, the administration and lawmakers on Capitol Hill are involved in concerted debate about what actions - if any - are needed to maintain and modernize the nuclear stockpile of the US.
On one level, the outcome of this debate could have a profound effect on the nature of the nation's nuclear deterrent. On another level, it could also influence the attitudes of other nations toward US nonproliferation efforts. This could be seen as early as next month, when a Nuclear Nonproliferation Treaty (NPT) review conference opens at the UN in New York.
"Washington still maintains a large nuclear arsenal designed for the cold war, and it fails to take into account the current impact of its nuclear policies on those of other governments," writes Clinton-era Director of Central Intelligence John Deutch in a recent issue of the journal Foreign Affairs.
Currently the US maintains a stockpile of around 5,000 active nuclear warheads, according to estimates from experts outside government.
Under the terms of the Strategic Offensive Reduction Treaty struck by President Bush and his Russian counterpart Vladimir Putin two years ago, that figure is supposed to be reduced to between 1,700 and 2,200 deployed weapons by 2012.
Mr. Deutch believes reductions could go even further than that. He would cut the arsenal to fewer than 1,000 warheads, which he says would be enough to counter the nation now most likely to try and match US capability: China.
"China ... is thought to have a total inventory of 400 nuclear weapons, including a small but growing ballistic missile force capable of reaching the United States," Deutch writes.
But for some other nations it is not just the size of the US arsenal that is critical. It is also the extent to which plans call for that arsenal to be refurbished and modernized.
In part, this is so because of the bargain struck under the (NPT). Signee states without nuclear weapons agree not to acquire them under the treaty. Signee states with nuclear weapons agree not to transfer them to anyone else - and to work toward eventual elimination of their own arsenals.
"The majority of the countries that belong to the NPT today are not confident that the nuclear weapons states intend to fulfill their NPT pledge to eliminate nuclear weapons," says Daryl G. Kimball, executive director of the Arms Control Association.
Among the things these critic countries point to are plans that indicate that someday the US might build new types of nuclear devices. In this regard one project now stands out: the earth-penetrator warhead, or so-called "bunker buster" bomb.
Under this program, the US is studying the feasibility of taking the current B83 bomb, putting a very hard case on it, and controlling the manner in which it strikes the ground very precisely, so that it can penetrate a few meters into the ground and remain intact before exploding.
The administration is requesting $4 million for its bunker-buster study in the fiscal 2006 budget, and anticipates a further $14 million request for fiscal 2007. The program faces resistance in Congress, where some powerful lawmakers have blocked previous attempts to fund it. The White House is trying again, because Secretary of Defense Donald Rumsfeld personally reviewed the program and directed the money be put back in the budget.
"He did this not because he's particularly interested in developing a new weapon, but because there are adversaries who are building deeply buried facilities, and it is unwise for there to be anything that's beyond the reach of US power," said Linton Brooks, the administrator of the National Nuclear Security Administration, at a Senate hearing on April 14.
Another effort critics view with suspicion is the Reliable Replacement Warhead program (RRW). Under RRW scientists at the US national labs are studying replacement parts for current warheads. These parts might change the nature of some warheads, which were designed 30 years ago. During the cold war, the military wanted lightweight and tremendous explosive power in its nuclear weapons. Today, the desired qualities might be instead sturdiness, reliability, and lower cost.
Administration officials say that the focus of this program is to extend the life of current warheads, not develop whole new categories of weapons. Nor will it lead to a resumption of nuclear tests, they say, since in essence they are looking at making existing weapons simpler and more robust.
Critics aren't so sure. Among other things, they worry that the nation's nuclear scientists will inevitably want to test their new devices if they differ much from existing designs. The administration is also requesting money to reduce the time it might take to ready the Nevada Test Site from 24 to 18 months, they point out.
"The program could morph into a program to develop new nuclear weapons capabilities," says Daryl Kimball of the Arms Control Association.