What will we remember a year from now about the raid on Libya? Weinberger's line: that sickle-shaped line he drew on the night of the raid tracing the flight path of the U.S. planes that struck Libya. The head of the sickle is at Lakenheath air base in England. The base of its handle is in Tripoli. And the arc extends out into the Atlantic -- repelled by France and Spain and Portugal -- and down through Gibraltar to the Mediterranean.

Weinberger's line divides the Atlantic alliance in two. Margaret Thatcher chose our side of the line and asked the right question: Why was Sgt. Kenneth Ford, the American soldier killed by the Berlin bombing, in Berlin in the first place?

Sgt. Ford and his 358,000 fellow American soldiers formed a tripwire. Both sides know that NATO cannot withstand a conventional attack from the Warsaw Pact. The main purpose of American troops in Berlin is not to stop a Soviet invasion, but to die in one. In order to get to Europe, the Soviets have to kill Americans. Which forces America to go to war for Europe. And not just any war, but likely nuclear war.

So: If Ford dies at the hands of those who want to do Europe harm, the United States goes to war, perhaps even to suicide. Instead, on April 5, Sgt. Ford dies at the hands of those who merely want to do America harm. Europe's response? Weinberger's line.

That was last week. This week, another response: a joint decision on sanctions. Not military or economic, mind you. The allies refused even to close Libya's foreign military bases, which are lightly disguised as embassies. Instead, they will restrict the number and travel of Libyan "diplomats" stationed at those embassies. They remain open for business, their principal business these days being the murder of Americans.

Oh, yes. And Europe has decided that a Libyan expelled by one country for terrorist activities would not be permitted to take up a post in another. Pseudo-actions of this kind can break alliances. Alliances always involve unequal burdens. But few can long survive the vast disproportion in NATO.

Nor the mendacious rationalizations that accompany European complacency. Former French foreign minister Michel Jobert, explaining France's refusal to give the U.S. planes overflight rights, gave a characteristically French response: We did not agree with you, so we did not follow you. C'est tout.

Denis Healey, foreign spokesman of Britain's pacifist Labor Party, felt obliged by Anglo-Saxon tradition actually to present a case. He claimed that the U.S. attack would not deter terrorism. In fact, states, for which terror is necessarily only one of many interests, are quite likely to be deterred by punishment. (Israel, for example, has completely eliminated state-sponsored terrorism from Egypt, Jordan and any terrorism coming across the Syrian border. The main source of anti-Israeli terror is Lebanon, where there is no state to be attacked and deterred.)

But even if Healey is right, it is simply wrong to judge the Libya raid solely on the grounds of deterrence, on whether "it works." There is the question of justice. The United States defended the raid by appeal to Article 51 of the U.N. Charter, which permits acts of self-defense.

Now, this is a valid, but very narrow rationale for an act so obviously just. Yet the administration felt obliged to invoke it because in our day the morally numbing language of international law has displaced traditional notions of natural law.

Why is it right, in domestic law, to punish a murderer? Not simply because of the Constitution or a law passed by Congress, but because it is a universal, human -- natural -- sentiment that such evil be punished. The same moral sentiment applies to collective acts of murder, which is a good definition of state- sponsored terrorism.

That is why justice "feels good." Sophisticates like Healey and Jobert are offended by the notion that ordinary people derived satisfaction from the U.S. retaliation. In part, justice does satisfy a certain atavistic urge. But it also satisfies a deeper feeling: that there is a moral equilibrium in the world that must be maintained, that unpunished evil disturbs that equirium, and that too great a disequirium makes life morally intolerable.

Euromendacity of the Healey-Jobert type will have two effects. First, the good news. After Libya, it is going to be very hard for American isolationists to try to prevent American action everywhere in the world by demanding that we first "consult with the allies." It is now clear to all that this is merely a way of advocating total inaction without appearing to do so.

We know that our allies are going to counsel restraint, i.e., passivity. Demanding that American allies lead (as in Central America) or act in concert with us (as in Europe) is to guarantee American paralysis. Imagine Grenada today had we entrusted its fate to, say, Contadora.

The bad news is that the continental drift in the Atlantic alliance will be vastly accelerated. Americans will not long assent to tripwires and suicide pacts if this is their reward. What starts with the withdrawal of American tourists ends in withdrawal of American soldiers.

Europeans believe that, now that America is a superpower, a return to isolationism is impossible. They are wrong. And if a look at American geography and history does not convince them, they might try meditating a while on Weinberger's line. Americans will be meditating on it for a long time.