GUERRILLA WARS, in a man ner of speaking, are recession proof.

There have been dozens of them in the last half-century, through good times and bad. They are relatively easy to start. Ernesto Guevara Lynch -- the "Che" of the legends -- thought a nucleus of 30 men was adequate. They require little or no capital. The necessary weapons ordinarily are available on the best of terms: no money down and no repayment. There are willing suppliers among the great powers, their proxies and surrogates. Operating costs are minimal. There are no payrolls to meet. Supplies can be liberated in the countryside.

The work has its attractions. It is less arduous and monotonous than laboring in the fields. It offers, in many cases, more variety and stimulation than village life or the academic grind. It is a potent outlet for grievances, aggressions and political ambitions. Ordinarily there is substantial leisure time and sometimes unaccustomed comforts. Guerrillas in Angola have organized soccer leagues and typing classes. In Zimbabwe in the late 1970s a good deal of beer was consumed in quiet villages in the bush, and thousands of potential fighters spent the entire war at ease in Zambia.

There are hazards, of course, but they are often overstated. Conventional warfare, pitting masses against masses, is a bloodier game. Guerrilla war is hide and seek. Each guerrilla killed or captured in Malaya required an expenditure of $200,000 by the British. In two years of guerrilla activity in the Sierra Maestra, the forces of Fidel Castro and Guevara suffered fewer than 100 casualties. The armies at Antietam in the Civil War sustained 23,000 casualties in a single day.

Communism and guerrilla war have been linked for years in the popular political perception. But communists have never had a monopoly on the art. Today, some of the most productive insurgencies are being waged against communist or Marxist regimes. In Marxist Mozambique, guerrillas sustained by South Africa have cut the country in two and are wreaking havoc with the economy and with government control in much of the countryside.

In Marxist Angola, Jonas Savimbi's guerrillas control more than a third of the country, interdict the main transportation lines and have created a government infrastructure in liberated areas. All this despite the presence in Angola of 25,000 Cuban troops who have shown no particular stomach or aptitude for counterinsurgency.

Marxist Ethiopia, also well-stocked with Cuban forces and Soviet advisers, has three insurgencies on its hands and has dealt successfully with none of them.

In Afghanistan, 160,000 Soviet troops have been futilely sparring with guerrilla forces for nearly four years.

It is the same in communist Cambodia, where 150,000 Vietnamese troops are mired in combat with various insurgent elements.

Guerrillas, contrary to some popular myths, are not unbeatable. They lose some and win some. The PLO, for the time being at least, has been emasculated by the Israelis.

The British won out in Kenya and Malaya and are unlikely to be overcome by the Irish Republican Army.

Black Panthers, Weathermen, Puerto Rican terrorists and the Posse Comitatus won notoriety in the United States, but the republic was never in peril.

Thailand, the Philippines and Indonesia have run highly successful counterinsurgency operations.

Guerrillas operating in Laos and Vietnam are more nuisance than threat.

SWAPO guerrillas in Namibia have been embarrassingly ineffective against the South Africans.

No guerrilla movement has ever prevailed in South America. Che Guevara twice tried to "export" the Cuban revolution, once in the Congo and once in Bolivia. The Congo expedition was a farce and was quickly abandoned; the Bolivian expedition was a disaster that cost Guevara his life.

One of the crucial factors in the outcome of guerrilla wars is endurance, not only on the part of the combatants but on the part of their sponsors and suppliers. The Western democracies, in that respect, are not well-suited for these affairs. They must answer to public opinion that makes fine distinctions between deserving and undeserving clients and to public impatience with small wars that seem to have no end.

The involvement of the United States in the guerrilla wars in El Salvador and Nicaragua is of fairly recent origin, but political support for these adventures already is wearing thin. Non-democratic societies are more reliable partners in such conflicts; the humanitarianism of their clients is an irrelevant consideration. Thus, their record of keeping open- ended commitments is impressive. The Cubans, with no national interest involved, have maintained large forces on the African continent for seven years without visible domestic dissent.

The democracies sometimes utilize surrogates to overcome or minimize internal political restraints. Arms are reaching guerrillas in Afghanistan without line items in the federal budget. Saudi Arabia is providing substantial assistance in support of U.S. objectives in the Horn of Africa. Israel is reported to be providing arms to the contra guerrillas in Nicaragua.

Sometimes there is another option for the West in these Third World conflicts: sit them out. When the guns are silent and the "revolution" is won, the reality of governing rears its head. People must be housed and fed. Economies must be built. Trading arrangements must be established.

Whence will the manna come? It is not likely to come from the Soviet Union, as a number of Marxist and pseudo-Marxist regimes have learned to their sorrow. The Russian generosity with guns is not matched by its generosity with rubles. Angola, Mozambique, Ethiopia, Zimbabwe and even Vietnam turn to the West with begging cups. The Sandinistas in Nicaragua, between denunciations of Yankee imperialism, keep their place in line for a resumption of U.S. aid.

No Soviet grants have been forthcoming, only tough barter agreements in which the Sandinistas swap cotton or sugar for cans of East European beans. It is one of the ironies of the contemporary world, that investments by multinational corporations are becoming more prized than crates of AK-47s.

There are no immutable lessons to be learned from guerrilla war in the 20th century except perhaps one: for all its popularity, it is an overrated enterprise, less fraught with historical consequence then the attention paid to it suggests.