S. Africa security moves draw fire

The South African government has unleashed a political storm by using the army to help local police control unrest in various black townships. All white South African males, including those who oppose the government and its race policies, are obliged by law to serve in the national Defense Force as soon as they finish their schooling.

If they do not, they are liable to go to jail. Even those with ''valid religious objections'' are obliged to take part in community service as an alternative.

The government's argument has been that the Defense Force is outside of politics and that its basic purpose is to defend the country from outside enemies.

Army chiefs describe the Defense Force from time to time as a ''shield'' that provides security for South Africa and buys time for politicians to bring about necessary reforms.

But opponents of conscription say the Defense Force is fighting an unjust war in defense of an unjust society. Apart from those who have been penalized at home for refusing to serve, about 3,000 men are reported to have left South Africa rather than join.

Their contention that the Army is a political weapon was strengthened when Louis Le Grange, minister of law and order, told the Transvaal Province Congress of the ruling white National Party about 10 days ago. He said there would be ''closer cooperation'' between the police and the Defense Force in controlling future domestic unrest that results mainly from political discontent.

Almost immediately, Army units were sent into Soweto, the huge black residential area near Johannesburg, South Africa's biggest city.

But, almost as quickly, they were pulled out again.

Although Mr. Le Grange and various Defense Force spokesmen discounted the idea that the troops had been withdrawn because of criticism about use of the Defense Force in a domestic capacity, the government's decision to involve the Army caused concern even among many of its own supporters.

Even the newspaper Die Burger, which supports the National Party, described the use of the soldiers as ''something of a surprise'' and said it hoped this would not be a ''continuing occurrence.''

Opposition spokesmen were more outspoken. Frederick van Zyl Slabbert, leader of the Progressive Federal Party, the major white opposition party in Parliament , said at the weekend that the government ''was paying with fire.''

He said nobody could object if the Defense Force was used to restore stability under conditions of extreme unrest or emergency, but it was unacceptable to use the Army to cope with ordinary social and domestic unrest, work that was traditionally done by the police.

This immediately involved the Defense Force in political conflict and intensified the whole controversy surrounding conscription and military service, Dr. van Zyl Slabbert said.

Ironically, the controversy erupted at the start of a nationwide anticonscription campaign that is based on the argument that the Defense Force is a repressive instrument of apartheid.

The spokesmen for this campaign have to choose their words very carefully. Under the Defense Act, anybody who ''by word or action'' does anything to ''incite, recommend, encourage, or otherwise cause any other person to refuse to render military service'' is liable to a fine of about $3,000 and up to six years in jail. Although only white mean are conscripted at present, it is widely anticipated that the government intends to extend compulsory military service to young Asians and Coloreds (people of mixed race).

These two population groups have recently been given the right to vote for representation in a new three-chamber Parliament. One of the reasons why so many Asians and Coloreds have rejected the new political system is that they want nothing to do with the government's ''apartheid army,'' which they say is an instrument to oppress them. They believe conscription will sooner or later be the price they would have to pay for their limited voting rights.