A Soviet diplomat, making an extraordinary appearance before a congressional committee, Thursday defended the Kremlin's handling of the Chernobyl disaster and brushed aside criticism of the worst nuclear power plant accident in history by reminding Americans of the failure of the space shuttle Challenger.
The Kremlin's approval of such an appearance--which has apparently happened only once before in the annals of U.S.-Soviet relations--suggested to American officials that Moscow wants to ease criticism here and in Europe over the accident and the clouds of radioactive fallout it has spawned.
Nothing said by the Soviet diplomat, Vitaly Churkin, was new, but his willingness to testify before Congress was seen as at least a minimal desire to explain if not placate Western public opinion.
Churkin, with youthful good looks and fluent English, denied that the Soviets have withheld information, deftly parried sharp questions from members of a House Energy and Commerce subcommittee and even lectured them not to "talk to my country in a commanding tone."
"I am not an expert on nuclear power; we do not have a nuclear power plant in our embassy," he said at one point, drawing laughter from the crowded hearing room.
But the exchanges were sometimes sharp as the congressmen pressed him for details and accused the Soviets of "stonewalling" about the accident. When pushed, Churkin pushed back.
Rep. Ron Wyden (D-Ore.), asked, "Can you tell me, in layman's terms, what happened, why it happened?"
Shot back Churkin, "Can you tell me in those same layman's terms how the Challenger (shuttle) accident happened? . . . It is something no one thought could happen."
With direct contact with Soviet officials almost non-existent, Churkin became an instant media star. At least two television networks pounced on him after the hearing and vied to schedule the Soviet diplomat on their evening news shows. Those familiar with Soviet propaganda grudgingly gave him high grades for his appearance before the committee.
"I couldn't believe my eyes," said one State Department official as Churkin's fresh face under prematurely gray hair appeared live on Cable News Network during the hearing. "I was impressed, despite the poverty of his material.
'He Was Smooth'
"He was smooth and polished, and easily turned the tables on those typical questions that congressmen ask," the official added.
Frustrated U.S. officials were also quick to note that the openness of the American system gave the Soviet spokesman a built-in advantage: No U.S. spokesman can hope to present this country's views on the Chernobyl episode directly to the Russian people.
A surprised State Department spokesman called Churkin's testimony to Congress "extremely unusual if not unprecedented." He tried to brush off questions about precedents as an "exercise in Trivial Pursuit."
A congressional historian found a precedent in a 1982 appearance by a Soviet trade official, Vladislav K. Navarov, before the Joint Economic Committee during a hearing on monetary and fiscal policy.
Congressional committees have subpoena power, but it extends only to U.S. citizens. In addition, diplomats have immunity that would allow them to avoid any such appearance if they or their government so chose.
Rep. Edward J. Markey (D-Mass), chairman of the subcommittee, invited the Soviet Embassy here to send a witness to a hastily called hearing on the nuclear accident.
The arrival of Churkin, who appears to be in his early 30s and later indicated he had been dispatched to the hearing on only an hour's notice, provoked near-universal astonishment. He is a second secretary specializing in arms control issues, and he has debated with U.S. officials before foreign affairs groups here.
He repeatedly told congressmen that he didn't have any technical details, falling back on generalities to answer questions during his two-hour appearance.
"Everything is fine with the water, with the air" in the Kiev region, he said, brushing aside reports of massive casualties. "There is no real reason for concern," he said soothingly.
Later, Rep. James H. Scheuer (D-N.Y.) asked why European leaders are so angry at the Soviets if the Soviet Union is as forthcoming with information as Churkin claimed.
"I find it offensive that people say you didn't do this or didn't do that without knowing the facts," answered Churkin. "If you want to talk to my country in a commanding tone, forget it."
In recent weeks, the Soviet Embassy has held two highly unusual press conferences to explain Soviet arms positions, with Churkin featured at both.