Americans like to think of themselves as simple folk, free of trickery or guile, operating a system so transparently open that the United States is left naked to the ravages of a duplicitous world.

It may seem odd, therefore, that 4 1/2 months into the Reagan administration, a nation which combines wisdom and subtleties learned over thousands of years with the collective craftiness of Confucius, Marx, Lenin, and Mao is still confounded by what is sees as inscrutable Americans.

The People's Republic of China at this stage, however, need not unduly blame cultural, political and intelligence-gathering barriers for its inability to penetrate the administration's China policy. It is only during the past week that the White House has seriously begun to decide, at the National Security Council stage, the stance it will take in its first major venture in any communist capital.

President Reagan met with the National Security Council at 1:30 p.m. yesterday, to consider issues involving China. For some time the State Department has pressed inside the administration for a more liberal interpretation of what U.S. firms can export to China in nonlethal "dual-use technology" -- equipment that can have both civilian and military uses -- beyond already authorized items such as certain computers, helicopters, communications equipment and radar sets.

On alternate days the administration has said it has "a China policy" and is "defining" or "refining" one. It cannot logically produce an operational China policy without an operational Soviet policy.

None of these deficiencies, Reagan administration officials insist, should impair the important soundings which Secretary of State Alexander M. Haig Jr. will take in Peking June 14-17.

"I thank God we don't yet have a China policy," one veteran American planner said in the privacy of his office. "If this administration agreed on one before it grasped the complexity of the problem, we could have had a national disaster."

No one at the White House, of course, would concede that. A senior staff member said acidly: "We are not meanderthals. There wasn't the slightest danger that we were going to reverse our primary interest in the PRC for the sake of our secondary interest in Taiwan. . . . Those were simply 'start-up' pains."

Among government professionals, there is a fairly broad consensus about what is trivial and what is paramount in the hardest decisions on China-Taiwan, with immense uncertainty about who actually will decide what.

At the top echelon, two men hold commanding leads in China experience. Vice President Bush headed the former U.S. Liaison Office in Peking during the Ford administration, and then was director of the Central Intelligence Agency. Haig served as deputy national security adviser to Henry A. Kissinger in the original "triangulation" of American-Chinese-Soviet policy, then led the advance party for President Nixon's "breakthrough" visit to China in 1972 after Kissinger secretly laid the groundwork.

Haig learned early and jarringly, however, that he does not hold anything like the sweeping writ of presidential authority that Kissinger enjoyed. But he acts fully primed for this mission. Only a few senior officials knew that during 1974-78, when Haig was supreme allied commander, Europe, he had unpublicized meetings with the two Chinese ambassadors to Belgium who were rotated through China's embassy in Brussels. Soviet intelligence in Brussels presumably discovered those liaisons. If that caused angst in Kremlin, Haig would not have been displeased.

Since becoming secretary of state, Haig has called close relations between the United States and China "a fundamental strategic reality and a strategic imperative."

Because Haig's views about the Russians so closely mesh with China's Deng Xiaoping's U.S. planners know they will find abundant "parallel" strategic interests. But many specialists believe that will be inadequate for Deng, whose understated present title is vice-chairman of the Chinese Communist Party Central Committee.

Deng, a recurring phoenix-like figure high in Peking's power structure, is mow 76. While he heads the dominant political faction, he is racing against time and the turbulence left by Mao Tse-tung to restructure the government and economy of nearly a fourth of the world population.

Haig goes to Peking knowing that Deng minced no words when Bush and Richard V. Allen, then national security adviser-to-be, went there last August to try to reconcile two glaring American inconsistencies: Reagan's campaign pledges to raise to an "official" level U.S. relations with the Chinese Nationalist government on the island of Taiwan which still claims sole legitimacy to rule all China; versus the breakfoff of all official American diplomatic relations with Taiwan in 1979 agreed to by the Carter administration.

An insider describes Deng in the Bush-Allen meeting as "impolitically brutal." That encounter is more-gently described on the Reagan side: "They boxed our ears."

On Aug. 25, 1980, behind a screen of semantics, Reagan jettisoned his insistence on "official" relations with the heirs of Generalissimo Chiang Kaishek on Taiwan. Reagan pledged to enforce "our official policy," notably, the Taiwan Relations Act of 1979, but said, "I would not pretend, as Carter does, that the relationship we now have with Taiwan, enacted by our Congress, is not official."

However, for Reagan, that was a switch to the fact that the law assuring Taiwan unofficial continuing American support was obviously "official." Reagan also pledged to "eliminate petty practices of the Carter administration which are inappropriate and demanding to our Chinese friends on Taiwan."

That 1980 statement is still cited as the authoritative Reagan position.

Deng and his colleagues had a comparatively easy time interpreting President Nixon in their terms of reference. For all his ardent anti-communism, Nixon eagerness to make a generational turnabout on American-Chinese hostility fitted squarely into Peking's far more furiously anti-Soviet doctrine.

In Reagan's case, although his political triumph literaly brought dancing in the streets of Taiwan, he apparently is perceived in Peking as a potentially-promising, but recalcitrant slow learner, with dangerous Taiwanese influences still clinging to him.

The signs of danger for Peking began to multiply during the Carter-Reagan transition, with newspaper reports about a new political cabal styled "The Madison Group." It was described as a "rightist network" of influential Capital Hill specialists determined to tilt the Reagan administration's foreign policy futher to the right than it was inclined to go.

In Peking, and in the People's Republic embassy on upper Connecticut Avenue, warning signs flashed, especially when Reagan transition staffers questioned the embassy's adaptability to a GOP-controlled Senate.

The embassy's acquaintanceship, not surprisingly, was with such moderate Republicans as Sen. Charles H. Percy, Sen. Charles McC. Mathias Jr., and Sen. Lowell Weicker. The embassy was advised to develop access to "real" Republicans, people in power.

That led embassy attaches to John Carbaugh, agent extraordinaire for shrewed bargainer Sen. Jesse Helms (R-N.C.), "keeper of the right-wing faith" for Reagan's conservatism.

Helms' influence is widely described inside the administration as grossly exaggerated and self-inflated. But Helms' main leverage is not insignificantly lodged in the right hemisphere of Reagan's mind and past. Peking was troubled enough to send its most sophisticated Americanologist, Ji Chaozhu, foreign ministry director of American affairs, to break ground with ultra-conservatives in Congress.

A high point in Peking's apprehension came in the inaugural ceremony.

Taiwan's press elatedly announced that senior officials had "official" inaugural invitations. Peking exploded.

Reagan spokesman denied that any Taiwanese had been invited in any official capacity. Only the PRC ambassador in Washington, Chai Zemin, would represent China. Taiwan's representatives had a batch of congressional invitations for the invited-guests section of the inaugural.

That fine distinction was going to be lost on, or scorned by, Peking's angry leaders. A behind-the-scenes "dis-invitation game" began in the State Department, the White House, and in the Reagan camp, to induce the most prominent Taiwanese to stay home, or pay the consequences for crossing up the new administration.

"We managed to reduce both the numbers and the level of Taiwanese participation," said a U.S. official. The most eminent invited guest, Lin Yangkang, governor of Taiwan Province, was "talked out of coming."

The secretary general of the ruling Kuomintang Party's central committee, Chiang Yien-si, reached Washington, but not the inaugural. He ended up in a suburban Virginia hospital. A spokesmam for Taiwan's mission here insisted that Chiang "was really sick; he caught a bad cold in New York."

The mini-crisis, in which no official saw any humor, subsided. But a drumfire of press attacks in China on U.S. relations with Taiwan has warned that they endanger all ties, and explicitly, parallel strategies "to cope with the Soviet challenge."

Peking's leaders simultaneously operate at a subtler level, although its press has been flaying Edwin Meese III for expressing administration determination to employ a key section of the Taiwan Act that permits sales of "defensive" weapons to Taiwan.

Nevertheless, the China News Agency, Xinhua, reported totally deadpan, under a Washington dateline of May 28.

"Chinese Ambassador Chai Zemin and his wife gave a banquet this evening in honor of Counsler to the President Edwin Meese III, White House Chief of Staff James A. Baker III, White House Deputy Chief of Staff Michael K. Deaver, Assistant to the President for National Security Richard V. Allen and their wives. The banquet proceeded in a warm and friendly atmosphere.

"Host and guests in their toasts wished the relations of friendship and cooperation between the two coutries continuous development . . ."

As a Chinese Marxist-Leninist ideologue might say: "Dialects govern life; everywhere there is thesis and anti-thesis, resulting in synthesis." At least that's what the doctrine maintains.