I recite all this stale history for the benefit of Stephanie Nolen, The Globe and Mail's correspondent among the Kurds in northern Iraq. Ms.

Nolen reports on having recently had the unusual experience of having to defend her country from criticism by the locals, for having opted out of the American-led war against Iraq. (Apparently, in that part of the world, people actually welcome an American invasion.) She made a game try at it. "The people of Canada," she began, "understand that Saddam is a dictator, and that the Kurdish people, like many other Iraqis, have suffered terribly under his regime." But. But "what we object to is unilateral action by the United States.

We believe that if the Americans are allowed to decide today that Mr.

Hussein must go, they may decide next week that it should be the leader of another country -- perhaps it will be Canada who annoys them, because we will not give them cheap access to our forests or our water." Stephanie, Stephanie. Have you forgotten? It could not happen.

We have a treaty.

But Ms. Nolen is far from alone. Probe a little beneath the surface of any critique of the war, and you will find the same anxiety: that this is just the start, that America has let slip all civilized restraint, at last daring to assert what previously it had only dreamed of -- empire. Rick Salutin, also writing in the Globe, sees the liberation of Iraq as "the first in a limitless chain of assertions of U.S. power." The Independent newspaper wonders whether the war has "a sinister, wider purpose, warning other rogue states, and perhaps other states, too, that this is what they can expect if they trouble the world's only superpower?" (Emphasis added.)

The notion that this conflict heralds the arrival of the American Empire is by now a commonplace. Even America's friends, such as Niall Ferguson or Michael Ignatieff, urge it to embrace the title. It is, they say, an "empire in denial." Some on the American right have taken them up on it, if only for the shock value. Max Boot, fellow at the Council on Foreign Relations, likens it to gays who embrace the "queer" label. Aren't we naughty?

No, just silly. An empire is an explicit scheme of territorial aggrandizement, born of military conquest and maintained by force of arms. The conquered territory is wholly absorbed within the legal and administrative structure of the imperial power. Most important, this arrangement is permanent. Empires don't go home.

There is no comparison with what the Americans are attempting in Iraq, or even the more far-reaching ambitions of the administration hawks for reshaping the Middle East. At most, they hope to displace the rulers of a small number of dictatorships that, like Iraq, have been waging a low-intensity war upon the United States and its citizens for many years -- a situation American governments of both parties have put with for far too long, and which no American government of either party would accept after Sept. 11.

In the case of Iraq, this new assertiveness has taken the form of a willingness to go to war (though just barely: say what you will about Colin Powell, Tony Blair and the United Nations, but without them George W. Bush would never have been able to win the support of a majority of the American people for war). But no one sane believes that the Americans intend to permanently annex these territories, as the 51st states and beyond.

"Empire" may be useful shorthand for a situation of unrivalled American power, together with a willingness to use it. But that's not, in fact, what the word means. Rome was an empire. America, whatever anyone says, is not Rome.

In most respects, America's power has nothing to do with military might. It is found in the richness of its economy, the vigour of its intellectual life, the appeal of its culture. It also wields military power, of course, on a scale that dwarfs any rival. But it is difficult to see how anyone could seriously view this as a threat -- anyone that is, that does not wish it ill. One has only to look, in support, at how that power has actually been used. I have mentioned before that the United States is the only country ever to ask the world's permission to use its own forces: in Korea in 1950, and again in 1991, in Kuwait. But it is worth repeating the reasons it was deployed in both cases: to defend other countries from being annexed by bestial dictatorships; to halt the growth of other empires, not to embark upon its own.

Well, that's two examples. Big deal. But the pattern has been repeated again and again and again. Freedom House, the human rights group that rates the democratic and liberal credentials of states around the world, lists 85 countries as "free." (Another 60 are classed as "partly free.") Of these, by my count more than 30 owe their freedom directly to American military power. There are the countries liberated from totalitarian rule in the Second World War, and sheltered from it ever since: France, Belgium, the Netherlands, Norway, Denmark, Greece, Austria, Germany, Italy and Japan. There are the countries of Eastern Europe, who would still be behind the Iron Curtain had the United States not first contained the Soviet Union, and ultimately outlasted it: Poland, Hungary, the Czech and Slovak republics, a dozen or more in all. There are Taiwan and Israel, lonely outposts of freedom who wouldn't last a minute without American support. And there are the countries in the United States' own backyard: the Dominican Republic, saved from a communist takeover in 1965; Grenada, which was threatened with the same in 1983; Panama, which was freed from the narcocrat Noriega in 1989. In every case, as soon as the troops were done, they came home.

I realize that American power has been used to less benign ends. Just as the West made parley with the Soviets to defeat the Nazis, so the United States acquired some unpleasant allies in the darkest days of the Cold War, a rogue's gallery of clients that included Saddam himself.

But that was decades ago. And whatever blemishes there may be on the U.S. record, it is incontestable that it has been on balance a force for freedom.

Empire? The last permanent addition to American territory by force of arms was in the Spanish-American War, more than a century ago.

Empires don't go home.