We associate the possession of nuclear weapons with superpower status. The US and Russia have by far the largest nuclear arsenals, while Britain, France, and China also maintain respectable stockpiles. When India tested its first atomic bomb, this was understood as, in part, expressing an aspiration to be recognized as a great power. The fact that a few lesser states such as Israel, Pakistan, and North Korea have nuclear bombs, and past efforts of countries like Iran or South Africa to build them, strike us as worrying deviations from the norm, as "proliferation" which needs to be constrained.
If you think about it, though, this situation is decidedly odd. Logically, one would expect that almost every technologically-capable country -- seventy or eighty countries at least -- would have nuclear weapons.
Nuclear weapons are not difficult for a reasonably-advanced, moderately-prosperous country to build. The technology of Hiroshima-style fission
bombs is now 74 years old, and H-bombs (typically several hundred times as powerful) are almost as old. The necessary
science and engineering are widely understood.
The H-bomb is
the ultimate peace-keeping mechanism. Nothing else in history has been so effective at preventing large-scale conventional wars. Take Israel, for example. From the country's independence in 1948 through 1974, a 26-year period, the surrounding Arab countries launched several wars aimed at overrunning and destroying it. From 1974 until today, a 45-year period, no further such wars have happened, though terrorism has persisted. What changed? It became generally known that Israel had a substantial nuclear arsenal (actually the first bomb was
probably built in 1967, but it takes time to develop a large force and delivery systems). Since then Israel has built probably around 200 warheads, which are deployed on submarines, meaning they would survive even if Israel were destroyed, so they could still retaliate. No sane government would start an all-out war with Israel. What's the point of starting a war when
winning would mean getting annihilated?
There are plenty of other cases where one would logically expect countries to build nuclear bombs as a deterrent. Japan, South Korea, and Taiwan all face a potentially serious threat from Chinese expansionism and North Korean belligerence; all three are highly technologically advanced and could easily build substantial nuclear arsenals. Saudi Arabia and Iran maintain a bitter rivalry; each side could deter an attack from the other with nuclear weapons. Two dozen countries in Europe have faced an existential threat from the USSR during the Cold War and from Russia today, and the majority of those countries are nuclear-capable. The world is full of local rivalries or tense situations -- Greece-Turkey, Brazil-Argentina, Indonesia-Australia, etc. -- which at various times might logically have motivated both sides to seek the ultimate deterrent.
Remember, you don't need a huge arsenal to deter even a superpower. Not even Russia or the US would be likely to invade a country that could wipe out, say, just five major Russian or US cities. Notice how there is no credible threat of a US military attack on North Korea, which has a few nuclear bombs, but such threats have been frequent against Iran, which has none. Every other government on Earth can see this and grasp the implications.
So why don't we live in a world with dozens of nuclear-armed countries? Non-proliferation efforts have played a role, but what allowed such efforts to work was the availability of an alternate means of establishing security -- guarantees or informal agreements from the US. The East Asian democracies and most western European countries didn't build their own nuclear weapons because they were assured of the shelter of the US "nuclear umbrella" -- US military protection, and if necessary nuclear retaliation, if they were attacked. The exceptions prove the rule. Pakistan has never had such a credible guarantee in case of war with India; Israel, after the Holocaust, would never allow itself to depend on others for security; and the US has no conceivable interest in protecting North Korea.
But the current system only works as long as other countries -- potential aggressors as well as countries which accept our protection -- regard US guarantees as credible. This is the real reason why Trump's
shredding of relationships with our allies, and repeated questioning of long-established alliances, is so important.
If you were a Taiwanese leader or defense official, with Taiwan's security in case of a future Chinese invasion threat as your top concern, would
you feel comfortable relying on US help, the way Trump has been talking and behaving? Or would you be more and more conscious that an independent Taiwanese nuclear arsenal, if it were large enough to credibly threaten even a few major Chinese targets, would reliably deter the threat indefinitely without any further need for foreign help? How about Ukraine? That country has never been offered security guarantees, and recently Russia has seized two substantial parts of its territory. If it had had nuclear weapons all along, that would not have happened; if it built them now, it could secure what it still has. Finland? Estonia? I don't know whether such small countries could afford a nuclear program, but if they could, or could acquire bombs in some other way, it would be the one thing able to completely eliminate the threat of conquest and enslavement.
It would be astonishing if secret discussions along these lines were not already happening in quite a few capitals. If Trump is re-elected, and perhaps even before the election in some cases, talk could well flow into action.
Even if Trump loses next year, things will not just "go back to normal". Other countries worry that if the US elected Trump once, it might elect someone like him again. In the long run, a world with far more nuclear-armed states may be Trump's most important legacy.
