Deadline for Angola?

THE case of Angola shows that foreign policy is a delicate and sometimes confusing art, not easily reduced to simplistic formulas. Angola is at the vortex of a debate now going on in the United States over when, where, and how Washington should intervene in trouble spots around the world, particularly communist-threatened ones.

At one end of the debate are those proclaiming a policy of nonintervention. At the other end of the argument are those who urge instant, and often military, confrontation with regimes under communism's sway.

But the countries involved are often different from each other. For instance, Angola, Nicaragua, Afghanistan, and Cambodia all have one thing in common. In each country, bands of resistance are battling Marxist regimes. But the circumstances vary widely. In Angola the Marxist government is somewhat pragmatic. In Nicaragua it is militant, abetted by Cuba, and exporting revolution. In Afghanistan the freedom fighters face an occupying Soviet army. In Cambodia the problem is occupation Vietnamese-style, e ncouraged by the Soviet Union.

The American response is varied. To the resistance in Angola the US at present sends no aid. To the ``contras'' opposing the Nicaraguan regime, the US sends nonlethal aid. What the US sends to the Afghans fighting a Soviet occupation is not a matter of public record, but it is presumed to be substantial and lethal. To selected Cambodian forces battling Vietnamese occupation, the US has been sending humanitarian aid.

If all this sounds a little confusing, it is. In addition to weighing a variety of factors in each case, there is also the overall relationship between Washington and Moscow to be taken into account. Both sides are groping for an improvement in that relationship. In the light of this, the United States must make careful judgments about when to use diplomacy, when to use aid, when to use military hardware.

A further complication is domestic politics. Those who urge the US to wag the big stick at South Africa and the Philippines are not necessarily in favor of intervention in Nicaragua. Those who think the US is correct in aiding resistance to Soviet occupation of Afghanistan may not agree with aiding resistance to a Marxist regime in Angola. And so on.

Angola presents the Reagan administration with a particularly complex decision. To aid, or not aid, UNITA, the guerrilla organization that battles the Marxist government, is a question that has divided people of goodwill and reason.

When Angola won independence from Portugal, it installed a Marxist regime. It invited Cuba to send thousands of troops to Angola. The Soviets dispatched advisers. But this military apparatus has failed to quell UNITA, which controls about 40 percent of the country and is headed by a pro-Western guerrilla leader named Jonas Savimbi.

Once barred from sending aid to Mr. Savimbi, the United States is now legally free to do so, and the debate is on as to whether it should.

Savimbi already gets aid from China, Zaire, Morocco, and some other Arab nations. But a complication is the substantial amount of aid he gets from the racist regime of South Africa.

Critics in the US say this puts Savimbi beyond the pale. Supporters say this does not make him a racist, it simply means he takes aid from where he can get it.

The US has been quietly talking to the Marxist leaders of Angola for some time. They have seemed interested in sending the Cubans home if the US can get the threatening South Africans to withdraw from neighboring Namibia. The South Africans have proved unwilling so far. But, given their internal problems and the drain that Namibia represents on their resources, they might be persuaded to think again.

The argument against overt aid to UNITA is that it might kill any US negotiations with the government in Luanda. Thus there is talk of covert aid.

The answer may be to give the Angolan government a deadline: Let's have movement on a political and diplomatic settlement, including a Cuban departure, within a couple of months, or you'll face the prospect of American aid to UNITA.