Zambian President Kenneth Kaunda said yesterday that the Carter administration had made a "giant tactical error" in allowing Rhodesian prime Minister Ian Smith to visit the United States, and announced that he will not support the latest British-American initiative for holding a general peace conference on Rhodesia.

Kaunda, the most pro-Western of black leaders in southern Africa, also vehemently attacked the United States and Britain for their responses to last week's attack by Rhodesian forces on guerrillas based in Zambia. The attack came while Smith and his back colleagues in the Salisbury government were in the United States.

"I stand amazed at the lukewarm condemnation of this wanton and dastardly attack on Zambia, a sovereign state, by the U.S. government and the British government," Kaunda said at a press conference before yesterday's condemnation of the raids by the State Department.

"All they have said really amounts to saying to Smith, 'We don't mind what you do.' In other words, it is support."

"I shall not forget that Smith gave those orders to shoot those innocent girls from Washington," he added, referring to the allegation of guerrilla leader Joshua Nkome that Rhodesian forces killed more than 100 unarmed women in an attack on one nationalist camp in northeastern Zambia last Thursday.

The Rhodesian military said it killed as many as 1,500 guerrillas in wide-ranging attacks on a dozen guerrilla camps in Zambia that began last Thursday. Nkomo has sharply disputed the number of casualities, and has made statements that place his estimate of the number killed at between 450 and 500.

In his statements before the press and diplomats yesterday, Kaunda not only showed anger at the Western response to the Rhodesian raid, but alos dealt a sharp blow to British-American diplomacy.

While Smith was in Washington, he and the black coleaders of his transitional government agreed to attned a conference with all other parties to the Rhodesia dispute, if that conference is organized with no "preconditions."

Now, however, leading figures in thee forces lined up against the Salisbury government - many of whom had favored earlier Anglo-American proposals for a general conference - are coming out in opposition to the latest initiative saying that the Western powers have dropped the condition that such a conference be limited to the original proposals.

Both Kaunda and Tanzanian president Julius Nyerere now have taken identical positions on the conference and nationalist guerrilla leaders are posing tough conditionsl for their attendance. Thus, the latest British-American initiative to bring an end to the war in Rhodesia appears to be heading for failure.

Washington and London have been left in the embarrassing position of having finally gained the agreement of Smith and his three black colleagues for a conference while having lost the confidence of the nationalists and the so-called front-line black African states.

"If the proposed conference is going to be based on the original Anglo-American proposals, Zambia will attend," Kaunda said. "If on the new Smith-Anglo-American proposals in Washington, Zambia says no."

While Kaunda made his despleasure with Washington's decision to allow Smith to visit the United States abundantly clear, he carefully drew a line between his feelings for Carter and those who advise the president.

"He [Carter] is an honest man that I love and have respect for," Kaunda said, also denying he is either "anti-America" or "anti-Britain."

"But his adminstration has made a giant tactical error in allowing the rebel [Smith] to go and give orders to move against Zambia from Washington."

Kaunda said he did not blame the Zambian defense forces for not having contained the Rhodesian attackers, since his government had deliberately chosen to invest most its revenues in the country's economic and social development and had not given the military sufficient funds or arms.

He admitted that Zambia was helpless to defend itself against the far superior Rhosesian forces, armed with South African and Western material.

He said Zambian intelligence had been aware the Rhodesians were planning to attack the day before but both he and Nkomo had assumed they would go strictly for military targets and not camps for refugees and women. The guerrilla military camps had been alerted and acquitted themselves well, he said.

He also noted that it took only five minutes or so for raiding jets to be over Lusaka, too shorth a time to allow Zambian aircraft to get off the ground to intercept them.

Many Zambians have been highly critical of the defense forces' failure to repel the attacking Rhodesian aircraft, including relatively slow moving helicopters, during the three-day assault on nationalist camps.

Kaunda said he had not intention of retaliating now by sending Zambian planes to bomb Rhodesian cities. He said he was a "realist" and knew that such an action would only escalate the war and drag South Africa and "Western vested interests" in on the Rhodesian side.

"If I sent our boys to go and drop bombs there, I would be committing suicide for Zambia," he told the audience of diplomats and high party and government officials.

I do not want to be responsible for the escalation of the war," he said. "I wouldn't be so stupid as to plunge my nation into chaos."

Asked if he was contemplating asking for outside African or Eastern bloc forces to help defend Zambia, the gray-haired Zambian leader said, "We are considering these options on a long-term basis."

He called upon Zambians, the frontline states and other African countries to "brace themselves for a long and protracted struggle" against the Rhodesian transitional government, which is supposed to lead to black majority rule by next year.

He also warned Zambians to be on the outlook for "internal enemies" and said security forces had arrested 18 foreign nationals in an area near where he said a Rhodesian aircraft had dropped a box containing explosives and land mines to be used to blow up bridges on Zambia's southern rail route.

He said the Rhodesians were planning to drive a wedge between Zambians and the nationlist guerrillas by getting people here to believe the guerrillas responsible for stopping traffic on the railroad.