Words matter, which helps explain the arms control community’s preoccupation with declaratory policies and treaties relating to nuclear weapons. But whatever phraseology emerges from the Obama administration’s Nuclear Posture Review and however long it takes for the CTBT to enter into force, the stock prices of nuclear weapons have never been lower for major powers.

This is partly due to favorable circumstances: The P-5 have far less to fight about now than in previous decades. Another significant reason for devaluation is the fact that nuclear weapons have not been used on a battlefield since 1945. Every year that passes without the appearance of mushroom clouds increases the penalties for crossing this threshold. Weapons that haven’t been used for six decades have decreased military value, which also diminishes their political value.

Nuclear weapon testing has become a surrogate for battlefield use, in the sense that every underground test is a demonstration of utility, and a reason for a potential adversary’s discomfort. Underground tests are therefore another key indicator of the value of nuclear weapons. Here again, stock prices have decreased markedly, as is evident by the number of test detonations in recent decades:

Decade No. of Tests
1960s 706
1970s 549
1980s 439
1990s 64*
2000s 2

*The 1990s figure includes 53 nuclear weapons test detonations conducted before the CTBT, plus a generous 11 declared by India and Pakistan in 1998 for a total of 64.

The permanent members of the UN Security Council haven’t tested since 1996 – an extraordinary stretch by historical standards. During the 1990s, only two states, India and Pakistan, tested nuclear weapons after the CTBT was negotiated. No country felt compelled to follow their regrettable example. And only one country – North Korea – has tested the Bomb since 1998. Pyongyang has received opprobrium, and little else, for doing so.

A fourth key indicator of devaluation for major powers is stockpile size. According to the best estimates compiled by Stan Norris and Hans Kristensen, the P-5 possessed the following number of nuclear warheads in these years:

Year No. of P5 N. Weapons
1979 53,360
1989 62,525
1999 33,859
2006 26,854

Yes, 26,854 is a very large number – and this doesn’t include stockpiles held by Israel, Pakistan, India, and North Korea. In the three most recent years that Stan and Hans have yet to tabulate, the arsenals of four of the P-5 have shrunk further. This trend line will continue, even with bumps in the road of U.S.-Russian relations. Bottom line: Four of the five major powers have never done more to uphold their end of the NPT’s bargain – but don’t expect sustained applause at the 2010 Review Conference.

Worrisome developments are also not hard to find, topped by Iran. Stockpiles are growing in China, Pakistan, India and perhaps Israel and North Korea. The IAEA’s Board of Governors has become polarized, with key non-nuclear weapon states undermining the NPT, rather than serving as its guardians. Other items could be added to this short list.

We are so in the moment – especially in this medium – that it’s easy dwell on the negative and to lose sight of facts and trends that are overwhelmingly positive. We all know that worst cases could be just around the corner. The worst of the worst is another battlefield use of a mushroom cloud. And I wouldn’t bet against additional underground nuclear tests. If renewed testing has cascade effects, the stock value of nuclear weapons will turn bullish.

Plus or minus, we’re in this for the long haul. In the meantime, every year that passes without a mushroom cloud or the testing of nuclear weapons is a good year – regardless of the language that emerges from the NPR or the infernal entry-into-force provision of the CTBT.