The questions now raised by both the White House and The Kremlin about each other's intentions may well detemine the relationship between the United States and the Soviet Union, and between East and West, for some time to come. If the Soviet excursions into Africa portend a new determination to assert a global Soviet role, as some Washington officials suspect, then new U.S. responses will be called for. If the delays in reaching a strategic arms agreement are, as Moscow suspects, due to U.S. decisions to withdraw some of the concessions Washington was previsiously prepared to make, then the Kremlin will have to ask itself whether an arms-limitation agreement is worth having.

President Carter's speech at Winston-Salem, which was deliberately publicized in advance as a hard-hitting reassertion of U.S. concern about national security in the face of a rising Soviet threat, has thus come at a time when the Kremlin's own concern was rising to new heights. But the answers to the questions the Kremlin is asking should be sought not so much in the president's speech as in PD 18, the presidential directive on national security and foreign policy that was referred to breifly in this column last week. The scope of PD 18 is much broader than the three issues - strategic arms, Europe and mobile forces for contingencies in such areas as the Persian Gulf - that were discussed in last week's column.

PD 18 was really the policy sequel to the much-discussed PRM 10, the presidential review memorandum commissioned last year by the new adminstration to assess the trends in the global balance of power and the national-strategy altenatives availiable to U.S. policymakers. Among the many military alternatives considered by PRM 10 was the possibility that a large part of West Germany might be overrn by Soviet forces, and the very fact that that was one of the options under consideration give rise to fears that the United States was prepared to accept some such eventuality. But PRM 10 was only a study of what might happen in a wide variety of situations around the world. PD 18, on the other hand, compressed into five concise pages the policy recommendations that emerged from that study.

PD 18 views the relationship between the United States and the Soviet Union in terms of two historical eras. During Era 1, which coincided generally with the period of cold war, the Soviet Union was relatively weak. The transition to Era 2, which began in the late '60s, saw the attainment of stragegy parity by the Soviet Union and the arrival of detente. At the same time, while Soviet conventional forces have grown to the point where the power of Soviet arms has greatly increased both in Europe and on the Chinese border, U.S. defense spending sapped by Vietnam, had declined in real terms. That was the analysis made by PRM 10, and PD 18 bases its policy recommendations on the conclusion that an overall military balance had emerged between the United States and the Soviet Union.

But unlike its predecessor during the Nixon administration, NSSM 3, which was concerned with the military balance, PRM 10 and PD 18 took a much broader view of the elements of national power and concluded that the United States enjoyed substantial advantages over the Soviet Union in a number of important areas. For the foreseeable future the trend in such fields as the economy, technology, political stability and diplomatic influence was likely to favor the United States. Era 2, described as a period of both cooperation and competition between the Soviet Union and the United States, was therefore seen by PD 18 as requiring the United States to maintain the existing military balance.

But PD 18 also lays it down quite clearly that the United States should use its nonmilitary advantages to induce the Soviet Union to cooperate on such matters as arms control and on regional and global issues. That means in effect that the tactics of linkage that have been debated so much are an integral part of U.S. political strategy as approved by the president last year.

Another element of PD 18 that Moscow can hardly welcome is its emphasis on promoting U.S. values, such as human rights and national independence. Washington has already shown that human rights can be used as political weapon against the Soviet Union, while the U.S. policy of improving relations with such East European countries as Poland, Hungary and Romania also helps to strengthen their desire for independence from Moscow. It is hardly a coincidence that during the recent Belgrade conference the three countries did not always toe the Soviet line as readily as Moscow might have wished.

The policies recommended by PD 18 have in fact been in operation since last summer, and the Kremlin has been able to deduce them by observing U.S. actions around the world. There can be no doubt in the minds of Soviet leaders that they have to reckon with a more active U.S. foreign policy, and with a somewhat harsher international climate, than during the Nixon and Ford adminstrations.

As seen from Washington, that is a response to the growth in Soviet military power and to the Kremlin's new willingness to take risks in using such power around the world. As seen from Moscow, it is a challenge to the legitimate assertion of the national interests of the Soviet Union as an emerging global power. If the policy review now under way in Moscow is to yield some realistic policy recommendations of its own, it will have to take into account the concerns that have led the Carter administration to issue the policy recommendations that form the core of PD 18.

The pravda article that replied to Carter's speech shows that the Kremlin is by no means certain of what the Carter administration's real attitude is. The Kremlin's first response, circulated in a Tass commentary, was to suggest that Carter had shifted the emphasis of U.S. policy back to the cold war. But the more considered response, in the form of a Pravda article, takes a step back, and merely asks whether Carter's remarks are to be "understood" as a shift of emphasis. The reply from Washington will also have to take account of some of the Kremlin's concern.