Moscow — With the latest burst of rhetoric between President Carter and Leonid Brezhnev leaving detente at an even lower ebb, the Soviet Union seems ready for a long period of tension over its Afghan intervention.
Indications here are that the Soviets are set on their military course and consider it more important, for the moment, than trying to encourage prospects for the SALT II treaty in the US Senate, trade concessions, science exchanges, and other contacts with the US and other Western nations.
The personal criticism of Mr. Carter by a Tass commentator Jan. 3 was predictable, given the language Mr. Carter himself used on US television Dec. 31 .
Mr. Carter said Mr. Brezhnev had given a "completely misleading and inadequate reply" to his own message of concern on the Moscow-Washington "hot line." Now Tass replies that Mr. Carter's television interview was "bellicose and wicked, and breaks all records of hypocrisy and lies."
However, observers point out that the Soviet words were issued at a comparatively low official level. They would have carried much more weight if issued by Pravda or the Foreign Ministry.
At the same time, each Western criticism of Moscow is being met with a propaganda blast that progressively adds new details without going into the aspects that trouble Washington, London, and other capitals the most.
The Soviets are using a number of standard propaganda techniques: They paint the previous Afghan leader in blacker and blacker terms (now accusing him of planning to use napalm to wipe out an entire Afghan tribe), while they accuse the United States of criticizing Moscow only to distract world attention from the American naval buildup around Iran.
There are discrepancies in the various Tass versions of events. The latest report says the late Hafizullah Amin "was going to execute all his political opponents" in the early hours of Dec. 29 but did not have time. Some read this as indicating Mr. Amin was still alive then -- though Tass reported Amin's death by quoting Kabul radio at 10 a.m. the previous day.
But Tass does not say who asked for the military aid or why it thought the guerrilla war was going so badly when Western governments felt there had been little recent change.
The issue here is whether the Soviets saw a target of opportunity in Afghanistan -- a chance to oust Mr. Amin, whom they had quarreled with repeatedly -- or whether they are signaling a break with the detente of the 1970 s and a new era of confrontation in the 1980s.
Some Soviet sources are being quoted here as saying that the Kremlin well knew what Western reaction would be, that the SALT II treaty was doomed anyway, and that President Carter's proposed five-year defense buildup was a clear American signal that times ahead will contain more confrontation than cooperation.
Some here believe Moscow felt the US simply would not do much about a country like Afghanistan, which Tass described Jan. 3 as having "nothing to do with the north or with the Atlantic."
Tass made the point after asking why NATO countries were so upset about events in Afghanistan, and went on to say NATO wanted to extend its sphere of operations now to the Mideast and the Near East. [Reuters news agency reports accounts from Pakistan's Jang newspaper indicated Jan. 3 that Afghanistan's Soviet-installed government had frozen bank accounts, stopped circulating the local currency, and was issuing Russian rubles.
[Quoting travelers reaching Baluchistan, the Pakistan province along Afghanistan's southern border, the newspaper said the measure was designed to stop funds reaching the tribal insurgents fighting the government.