President Bush’s basic vocabulary — good and evil, war and victory _ has always made his liberal critics uncomfortable. But the other week Bush seemed to be speaking to members of his own administration when he made it crystal-clear to the world that we’re fighting a “war” against terrorism. It’s not, as Defense Secretary Donald Rumsfeld has recently been nuancing it, a “global struggle against violent extremism.”

It’s a war: plain and simple. Of course, wars are neither plain nor simple.

They’re messy and unpredictable. But to his credit, the president seems to recognize — in his gut — that a shift in vocabulary will change nothing. A policy is either right or wrong.

So what are we to make of Rumsfeld’s re-labeling project, and the president’s very public rejection of the new vocabulary? It has settled one thing, for sure:

Bush has a firmer handle than even Rumsfield on how empires think and act.

And I don’t mean that as a criticism.

It’s time for us to accept and defend our imperialism. Imperialism has received bad press for most of the last hundred years. We think of pith helmets when we hear the word, and tiger hunts, and pathetic little bands in remote Indian provinces playing “God Save the King.” We think of a stiff upper lip that looks, over time, more like foolish bravado than noble resolve. We think of colonial hubris and the blind assertion of cultural superiority.

But ancient Rome _ always the brand name in empires _ is the better model.

Rome demonstrated that empires can be about much more than blood sports, tiger hunts, rapacious oil companies and military adventures in far-off places.

Empires can also stand for things that make the world a better place. Political stability, the rule of law, the virtues of political enfranchisement, the preservation of learning and the arts, and the respect for other cultures and religions: These are some of the better legacies left to us by the Romans.

The Romans pulled this off _ with all their faults _ because they believed in that quaint concept we call destiny. Americans, too, have always believed in a higher purpose. Four hundred years ago, John Winthrop described America as “a shining city on a hill.” Ronald Reagan echoed that language in speeches that resonated deeply with the American people. The liberal elites in America and Europe never understood the mythic power of Reagan’s rhetoric, just as they don’t understand Bush’s simple vocabulary today.

That disconnect is easy to explain. If you believe that history is the product only of material forces _ and is never nudged onward by some transcendent will _ then all this talk about destiny will strike you as, well, a bit spooky. Bush has embraced the transcendent view, and the clear-cut vocabulary of war that goes with it.

That certainty may creep out a lot of people, but this doesn’t keep the president from declaring, repeatedly and rightly, that we represent a force for good in the world. What we’re fighting for cannot be reduced to “one set of interests” struggling against “another set of interests” in a world of diminishing natural resources.

We are fighting a war over things that matter _ not the right to wear pith helmets, hunt tigers or drill oil wells in distant lands. We are fighting for ideals that transcend race, culture and religion: ideals of freedom and human dignity. And that’s the kind of “imperialism” we should be willing to defend.

(Michael A. Babcock, an associate professor of humanities at Liberty University in Lynchburg, Va., is the author of “The Night Attila Died: Solving the Murder of Attila the Hun,” Berkley Books, 2005.)