The policy of a pre-emptive military strike by one nation or nations upon another is inconsistent with international law - and for good reason. A strike on the grounds of self-defence may be justified if an attack is imminent. But unless troops are massing on the border, how can any state be sure this is the case? The only way is to rely on intelligence. The American-led attack on Iraq, justified on the basis of what turned out to be flawed intelligence about Saddam Hussein's possession of weapons of mass destruction, shows how easy it is to be wrong - with devastating consequences. It is therefore disappointing that Australia, a key ally of the United States, is not prepared to repudiate the doctrine even after signing a historic regional peace treaty. Instead, Foreign Minister Alexander Downer yesterday reasserted the right to launch a pre-emptive strike if, for example, terrorists in a neighbouring nation were planning an attack. Australia has long resisted signing a non-aggression pact with the Association of Southeast Asian Nations (Asean) because it would bar such a strike. Tuesday's news that Canberra had finally agreed to sign, in order to win a seat at the inaugural Asean East Asia economic summit in December, had raised hopes of a change of heart. The non-aggression pact requires members to agree not to interfere in the affairs of each other. Prime Minister John Howard repeatedly said Australia would not sign the document because it would conflict with other treaty obligations - principally with the United States. But he upset several Asian countries with consistent comments reserving the right to conduct pre-emptive strikes to protect Australian interests. It is understandable that Australia would want to be proactive in its preparations to meet the threat of a terrorist attack by Islamic extremists. As a member of the US-led coalition in Iraq it is a likely target. Last year a suicide bomber attacked its embassy in Jakarta, killing 10 Indonesians, and 88 Australians died in a terrorist bomb attack on a Bali nightclub in 2002 that killed 202 people. Mr Downer said yesterday Australia had told Asean members it understood it retained the right to self-defence. That is fine. And he added that if Australia faced the threat of a terrorist attack from the shores of an Asean nation, 'I can't imagine a circumstance where an Asean country itself wouldn't stop any such action'. If this is right, there is no need to reserve the right to launch a pre-emptive strike on the territory of such a nation. It is good that Australia has joined an important regional grouping, but sad that it has thrown away a symbolic opportunity to show some moral leadership. The pre-emptive strike is a dangerous doctrine. Events in Iraq have shown why. It should no longer feature on the foreign policy agenda of any responsible government.