By Roger Hardy BBC Middle East analyst

Four countries, long branded "rogue states" by Washington, now seem to be mending their ways.

Colonel Gaddafi opts for diplomacy - sign of a changed world

Libya has renounced weapons of mass destruction; Iran has accepted stricter inspection of its nuclear programme.

Syria is making up with its pro-Western neighbour Turkey; and Sudan may at last be ending its long-running civil war.

So are yesterday's rogues today's law-abiding citizens?

President George W Bush must be feeling vindicated.

His controversial get-tough policy towards what he regards as rogue states is undeniably bearing fruit.

In the space of a few months, the former Iraqi leader Saddam Hussein has been captured; Libya - in a dramatic U-turn - has said it is giving up its attempts to develop weapons of mass destruction; and Iran has agreed to more intrusive inspection of its nuclear programme.

Even Sudan's new seriousness about ending its civil war can be attributed, in no small measure, to sustained American pressure.

Saddam's example

Two big events have shaken up the leaders of these countries. One was the 11 September attacks in 2001, and the other was last year's war in Iraq.

Together, these events showed that the world had changed, and with it US foreign policy.

The fate of Saddam Hussein served as a grim warning of the lengths to which the Bush administration was prepared to go - even in the face of opposition from much of the world.

Less clear is how far Mr Bush can build on these successes.

Has Iran really abandoned the pursuit of nuclear weapons or merely bought itself some time?

Is it likely Iran and Syria will stop supporting the anti-Israeli group Hizbullah which the US brands as terrorist but they regard as a legitimate resistance movement?

Moreover the Syrians ask why they should abandon weapons of mass destruction unless Israel does so too.

Finally, if rogue states really are changing their ways, who should take the credit?