Although US Undersecretary of State Lawrence Eagleburger late last month forthrightly linked the Reagan administration's southern African policy with that of the Carter era, he refused to make any fundamental tactical alteration to the current policy of the United States toward South Africa.
Mr. Eagleburger told the National Conference of Editorial Writers that South Africa's political system was ''morally wrong.'' The US, he said, ''must reject the legal and political premises and consequences of apartheid.'' It rejects any attempts to strip south African blacks of their citizenship. It is ''repelled'' by the forcible removal of stable black communities to barren sites in the so-called homelands. It could not ''countenance repression of organizations and individuals by means of administrative measures like banning and detention without due process of law.''
These are strong and welcome restatements of traditional American official views of the South African political process. Mr. Eagleburger also called for regional peace and stability which will, he said, encourage ''essential change'' - a ''basic shift away from apartheid'' - in South Africa. Overall, the tenor of the speech should be applauded by those in the US and South Africa who hope for an intelligent modernization of the attitudes and actions of the country's ruling minority and rapid movement toward the essential, open, black-white dialogue that can alone propel South Africa down the road of evolutionary political development.
But Mr. Eagleburger did not demand mutual discussions between representatives of the majority and the several minorities that comprise South Africa. Instead, he said that ''Western policy . . . must focus on how various black groups acquire the basis and influence necessary to participate in a genuine bargaining process that produces change acceptable to all.''
He went on to say that American interests were best served by encouraging the change that was now under way. Subsequently, he correctly applauded change in the sphere of labor relations and then praised the government of South Africa's present intention to change its constitution to give some political representation to 2.6 million Coloureds (peoples of mixed descent) and .8 million Asians, without offering participatory crumbs to the country's 26 million Africans.
Yet Africans have overwhelmingly condemned the new constitutional changes, as have two of the opposition parties in South Africa's parliament. Prime Minister Pieter Botha has, in effect, slammed the final door on black political representation, denying often that the proposed changes are meant to be but a prelude to African advance. Mr. Eagleburger's speech lamely excuses and condones this omission as a temporary tactic.
Most of all, despite Mr. Eagleburger's critique of the system, his speech made no explicit or implicit modifications of the Reagan administration's existing policy of ''constructive engagement.'' Indeed, Mr. Eagleburger refused to endorse, even as a tactic, the congressional efforts now under way to bar American bank loans to the government of South Africa, to halt the sale of South African gold coins in the US, and to compel American corporations to follow the voluntary code of good citizenship to which most already adhere.
Not even over Namibia, the fulcrum of constructive engagement, did Mr. Eagleburger promise that the Reagan administration would toughen its stance, or make new demands on South Africa. He talked weakly about the need for Angolan ''reciprocity'' when it is South African obstinacy which has frustrated the American initiative. Further, Mr. Eagleburger asked all parties to make a contribution; South Africa should withdraw its troops from southern Angola as well as Namibia, and Angola should send Cuban troops home.
But, South Africa is by far the most powerful military force in the region, and has demonstrated its power in Mozambique, Zimbabwe, Lesotho, Swaziland, and Zambia, as well as Angola. Mr. Eagleburger did not promise to curb the exercise of South African power. Indeed, he promised more of the same constructive engagement which has so successfully encouraged South African forward military operations and the ''destabilization'' of the southern African region.
If the Reagan administration wants the kinds of profound internal changes that Mr. Eagleburger has enunciated so well, then constructive engagement will need to become an active as well as a passive policy. Mr. Eagleburger and his colleagues may therefore wish to find nonrhetorical ways to show the South Africans that they are serious about regional peace and internal change.