This would be in line with what the immigration agency calls its "deterrent" strategy, which makes the asylum process difficult enough to ward off "frivolous" claims.

"We're trying to get a better understanding of the risk at the lower numbers and whether we can still meet the deterrent strategy," said a senior Pentagon official involved in the study.

But you may learn the hard way that mutually assured destruction as a deterrent strategy only works when you are faced with a conventionally rational counterparty who values their own survival.

And non-state terrorist groups with nuclear weapons are "conceptually outside the bounds of a deterrent strategy and present difficult new security challenges".

Causing new worries in Washington and Beijing, Taiwan's leaders have recently spoken of developing a new, more aggressive deterrent strategy, with a goal of fielding offensive weapons including long-range missiles.

In order to confront dictators of his kind we must set aside the misleading lesson of our victory in the cold war, achieved by huge military expenditure on a deterrent strategy.

Another deterrent strategy involves marking valuable items by engraving an identification number on them.

The Border Patrol instituted the same deterrent strategy it used in San Diego to Arizona.

This hoped-for train of events would eliminate the flaw in NATO's deterrent strategy that the weapons were alleged to remedy.

However, the fundamental reason for rejecting the weapons in Britain or elsewhere in Europe lies in a flaw at the heart of NATO's deterrent strategy.