How revolutionary is newly-reelected US President George W Bush's unilateralism? From America's inception as a republic, the founding fathers forswore entangling alliances that might embroil the fragile country in dangerous Old World controversies.

Acting unilaterally, the US could prudently pursue its own interest, nurture its fundamental ideals, and define itself in opposition to its European forbears. Preemptive strikes are a strategy nearly as old as the US itself.

When Gen Andrew Jackson invaded Spanish Florida (1818), secretary of state John Adams told the Spanish ambassador that Spain's failure to preserve order along the borderlands justified US preemptive action. President T Roosevelt announced in 1904 that the US would intervene in the Western Hemisphere to uphold 'civilisation'.

President FD Roosevelt, too, did not eschew the preventive use of force. When Nazi submarines attacked the US destroyer Greer (1941), he declared: 'This is the time for prevention of attack'. Thereafter, German vessels traversing waters in the North Atlantic would do so 'at their own peril'.

Prior to Sept 11, the last strategy paper of the Clinton administration spelled out America's vital interests. 'We will do what we must ... ,' wrote the Bill Clinton's security team, '... to defend these interests. This may involve the use of military force, including unilateral action'.

Critics argue that Bush's unilateralism repudiates the multilateralism that flowered after WWII. These critics have a point, albeit one that should not be exaggerated. The 'wise men' of the Cold War embraced collective security, forged Nato, and created a host of other multilateral institutions. But they never repudiated the right to act alone.

Publicly, they affirmed US commitment to collective security and multilateralism; privately, they acknowledged that the US might have to act unilaterally. The US has taken anticipatory action to deal with real or imagined threats from Central America, the Caribbean, Southeast Asia and the Middle East.

In each case, policymakers employed the same rhetorical justification that Bush uses now: 'freedom'. The differences between Bush and his predecessors have more to do with style than substance, more to do with balance between competing strategies than with goals, with the exercise of good judgement than with the definition of a worldview.

Contrary to the public caricature, Bush's administration does not use preemptive war as its only, or even principal, tool. It has hesitated to act preventively in Iran and North Korea, calculating that the risks are too great.

It acts selectively, much as its predecessors did. Vietnam, like Iraq, was a war of choice. There is nothing particularly revolutionary in Bush's goals or vision. The US quest for an international order based on freedom, self-determination, and open markets has changed very little.