Television viewers watching videos of smart bombs knocking out precisely chosen targets in Yugoslavia may feel that they have witnessed the hi- tech equivalent of what Goethe saw at the Battle of Valmy in September 1792, when the artillery of the French republic swept aside the parade ground tactics of the antiquated Prussian army. Then he remarked: "From today and from this place there begins a new epoch in the history of the world. And you can say you were present at the time."
Nato's military action has radically changed the rules of the international game. In fact, they were torn up when Nato's cruise missiles and bombers went into action without UN Security Council approval. Even those who wholeheartedly endorse the humanitarian justification for the Nato action must be aware that, when the first cruise missile smashed through the thin skin of international law, the world's door was opened on to a void.
To get after the devil Milosevic Nato's leaders tore down the fragile edifice of international law. Even if we allow that their bombing campaign did not incite the Serbs to terrible retaliation against the Albanians in Kosovo, did they think through the precedent that was set? Thomas More cautioned his son-in-law Roper 500 years ago that cutting down every hedge and thicket to get after the devil would be self-destructive if he ever turned like a whirlwind on his pursuer.
Little battered brutal Serbia may not turn and, even if it did, could not hurt mighty Nato. But the world is not so small. Even if we accept that Milosevic will soon fall and a democratic Serbia come into being alongside a repopulated Kosovo, and even if we assume that Kosovo avoids the kind of murderous chaos gripping Chechnya as the KLA and its rivals settle their differences, a note of caution in the hour of victory - if in this case we have victory - is always valuable, if rarely welcome.
The combination of Nato's hi-tech firepower with the limitless possibilities for humanitarian intervention in our imperfect world sets alarm bells ringing. Unlike national interest, humanitarian intervention knows no natural limits. At times the Prime Minister's visionary language suggests that he supports Nato becoming a sort of Church Militant sending out armed missionaries to restore peace and justice globally.
Like most idealists, the prophets of the "New World Order" are oblivious to the doubts held by others. Isn't our high-minded motivation obviously sincere? Shouldn't that be enough to stifle reservations at home and abroad? Western leaders assume that their humanitarian instincts are shared by the rest of humanity. Unfortunately, that isn't the case. Perhaps because most of the world is still ruled by tyrants or only recently escaped from ideologically driven dictatorships, great swathes of humanity regard high- flown rhetoric with a jaundiced eye.
Modern global communications mean that what would in the past have been a terrible but local Balkan tragedy has become a universal event. But one whose meaning is not universally agreed by any means. For every voice applauding Nato's action there are at least as many decrying it as American imperialism. Americans are often baffled by this charge. Look at how willingly the world has adopted their popular music and films, their soft drinks and even their business methods. Sadly for America, humanity can imitate without affection. An Armenian student from the local American University told me last Sunday in Yerevan: "We like American styles. We like American music. We like Americans. But we don't want to be told what to do by America. We want to be independent."
If any Marxists still exist, they will recognise this bitter irony of globalisation. Unlike any previous hegemony, America faces rebellion from the very people who most imitate it outwardly. In the golden age of the British empire, an ambitious Indian lawyer like Gandhi dressed in the best Inner Temple style, and when he broke with Britain the starched collar and pin-striped suit went into the dustbin. As anti-American Chinese students show, it is perfectly possible to wear a baseball cap, jeans and a T-shirt and still utter sentiments worthy of a Boxer a century ago.
Ten years after the fall of the Berlin Wall, a phenomenon is rapidly developing which hardly existed behind the Iron Curtain before then - popular anti-Americanism. Decades of Communist propaganda from Berlin to Peking failed to produce any genuine hostility to Americans, but today on my travels around the ex-Soviet bloc, to meet it is routine. Suspicion, indeed downright disbelief, of American political motives is now widespread.
Bombing Belgrade confirmed for umpteen millions of people the idea that Washington seeks world domination. Who will be next is the question. Overnight, Ukrainians have gone from viewing Russia as the major threat to their independence to seeing the United States as the most likely aggressor; some Ukrainians are even demanding nuclear rearmament. The Chinese general staff has struck a popular chord by observing that Nato's method of attacking Yugoslavia's economic infrastructure, to cripple the popular will to resist, could set a trend in future wars. Indian strategists and even Brazilian colonels have written about how satellite-guided missiles might be used against their semi-developed infrastructure. India sees America as Pakistan's traditional ally, and the Balkan war as another justification of their A-bomb programme to deal with their own Kosovo problem in Kashmir. Is it absurd for Brazilians to fear that a future president Al Gore might not only put human-rights demands to them over their treatment of Amazonian tribes, but might even fight an eco-war against Rio de Janeiro to halt the destruction of the rainforest? That might have seemed outlandish in February; to many Brazilians it doesn't today.
By shattering the role of the UN Security Council in authorising third parties to take military action, Nato has created a world in which irrational fears - some more irrational than others - begin to seem almost plausible. The Russian mediator Viktor Chernomyrdin has predicted: "Even the smallest independent states will seek nuclear weapons and delivery vehicles to defend themselves." America and Britain have been bombing Iraq for eight years to stop Saddam Hussein getting such weapons. May other states now come on to the target list?
It is hardly surprising that America's European allies seem anxious to get in on the ground floor of the new arms race. The war has given a tremendous fillip to the idea of a European defence identity. Ironically, even as the EU leaders reiterate their commitment to Euro-Atlantic solidarity and bask in the reflected glory of the success of American hi-tech weaponry, the pressure for the EU to shake off its dependence on US leadership and firepower is bearing fruit. The Tory Eurosceptic cheerleaders of Operation Allied Force will find themselves out in the cold as pan-European arms conglomerates merge to facilitate the research and development to equip a pan-European army. Even before this war, the Europeanisation of the British armed forces was moving ahead rapidly, if surreptitiously.
Rickety old Antonovs have been providing the heavy lift for the British forces in the Balkans and carrying in aid. A European consortium will soon be producing its own military equivalent of the Airbus. That shouldn't be too difficult, though the quarrels about who gets to make which components will add to the cost. British Aerospace, meanwhile, wants to co-ordinate the production of our own smart bombs. That will be expensive, and the smart bombs may never materialise, but BAe will certainly pursue its ambitious plans. What if the EU succeeds in creating a viable defence identity and a genuine defence industry? Will we still suffer the tutelage of the Americans in Nato gladly?
The world will not be the same again. A decade after the bloodless end of the Cold War, far from rewriting the rules of international relations the West's victory may have abolished them altogether. Certainly the goalposts have been moved and no one can be certain where we will find them tomorrow. If peace is at hand, it could be the peace to end all peace.