On June 5, an amateur politician-turned-amateur diplomat in Stockholm fired off an excited telegram to the State Department with repercussions that show how eagerly the favor of Henry A. Kissinger is still sought.

Rodney Kennedy-Minott, U.S. ambassador to Sweden, reported in exultation that Kissinger, on his visit to Stockholm then taking place, not only endorsed U.S. foreign policy in general but also the emergin SALT II treaty. When we informed him about this telegram, Kissinger told us the tyro ambassador had exaggerated his position in one stance and misunderstood it in another.

From the sieve-like State Department, the ambassador's effusive report flowed into the streets of Washington. Republicans responsible for designing their party's foreign policy - reading Kennedy-Minott without benefit of Kissiner's explanation - were mortified. Was Henry running with the hares while hunting with the hounds? While collaborating with the Republicans in mordant critiques of the Carter foreign policy, was he also buttering up the president behind the scenes?

Even if Kissinger were an innocent victim in this incident, as is entirely possible, the ambassador's jubilation and the Republican dismay show with what intense scrutiny Kissinger's words still weighed. Both sides believe he may ulimately determine whether SALT II is ratified by the Senate.

Until the election of Carter, Ambassador Kennedy-Minott was an obscure college professor in California who dabbled in liberal anti-establishment politics. Lucky or smart enough to back Jimmy Carter early in a state where Carter ranks were thin, the professor was rewarded with the Stockholm embassy (causing gasps of surprise back in California). So it was that he took himself to the airport to greet Kissinger when the former secretary of state arrived in Stockholm as head of Chase Manhatttan Bank's international advisory committee.

Kennedy-Minott's excitement fairly leapt from his telegram to Secretary of State Cyrus Vance: "I met Kissinger upon arrived in Stockholm and we had a good chat driving in from the airport. He was personally most agreeable and appreciative that I met him."

Then the ambassador got to the really good news: "Even more importantly, he went out of his way to express his general agreement with the lines of the administration's foreign policy . . . and particularly told me of his admiration for the secretary [Vance] and his appreciation of the job he is doing. He several times stressed the fact of his approval of our policies."

Could this be the same Kissinger who is so apocalyptic in private conversation about Carters's conduct of foreign policy? Kissinger explained to us he had merely informed the ambassador that "I always support the president's policy when I go to a foreign country. I didn't say whetfer I agree or disagree with it."

Kennedy-Minott's telegram next reported on "a good fill-in" given him by "our Swedish friends" of Kissinger's talks with Prime Minister Karen Soder: "Again Dr. Kissinger gave support to the administration's foreign-policy positions in general. On SALT, he was relatively optimistic, saying he expected an agreement to be initialed by about September."

Considering Kissinger's private dismay with SALT's current state, what the ambassador described as "optimistic" might have been only realistic.

What came next, however, could not be easily dismissed: "In the discussion of strategic affairs, one of the Swedish participants asked about the possible effect of the 600-kilometer limit of submarine-launch cruise missiles on Swedish and Nordic security. But Kissinger dismissed this as not a serious question."

Was he truly pooh-poohing the notorious 600-kilometer limit on sea-launched cruise missiles agreed to by Carter negotiators, a concession Kissinger as secretary of state refused and now as an ordinary citizen privately condemned?

Not at all, Kissinger explained to us. The former professor from California had got things mixed up. The Swedish officials, displaying their national self-protection reflex, wondered whether 600-kilometer, submarine-launched missiles would be fired over Sweden en route to Russia. Kissinger patiently told them not to worry, that a 600-kilometer missile would not be fired at Russia at all. He indicated to us that his dismay over the U.S. concession is undiminished.

"The only point I have to make," Kissinger repeated to us, "is that when I go to a foreign country I don't criticize my country's policy." But Republicans wonder whether his praise, as cabled home by the grateful Kennedy-Minott, was a shade too abundant. Meanwhile, they have fingers crossed that he will end up with them on SALT and other great issues between now and the 1980 election.