FROM time immemorial great powers have had troubles with their small neighbors, and vice versa. It is in the nature of large powers to desire, and expect, deference from their small neighbors. It is equally in the nature of small neighbors to wish to be independent of their overpowering neighbors and, to that end, be chummy with some other remote great power.
The relationship between England and its neighbors inside the British Isles is a classic case in point. The Scots traditionally looked to France for help against England; the Irish looked to Spain when it was a great power in the days of the Armada, and then to Germany in more modern times.
Today the old pattern comes out in the reaching of Russia's small neighbors toward the United States for aid and comfort in their struggle for independence from Moscow, and in the reaching of some of Washington's neighbors toward Moscow.
The problem is always latent in the relations between today's superpowers and their respective small neighbors. It is acute right now in the relations between the United States and Nicaragua and between the Soviet Union and Afghanistan. The immediate question in this four-cornered situation is what President Reagan will do about the weapons Moscow is sending to Nicaragua.
One thing Mr. Reagan might do as counterpressure would be to step up the flow of American weapons to the Afghans. So far that flow has been unofficial and unavowed. It could be made overt, as is the flow of Soviet weapons to Nicaragua. Also, it could be increased. One limiting factor is the ability of the Afghans to use sophisticated weapons. Another is getting weapons to Afghanistan without compromising intermediate countries that are hardly eager to risk Soviet countermeasures.
One other and more direct method would be to blockade Nicaragua and forbid the transfer of more Soviet weapons to that country. But a blockade is an act of war. The government of Nicaragua is recognized as being legitimate by the community of nations, including America's NATO allies and by even the friendliest of Latin American governments. The US recognizes the government of Nicaragua. There is a US ambassador in a US embassy in Managua, its capital.
Is it really necessary, or even becoming, for the mighty US, with its 237 million people, to make war on a Central American country of only 3.2 million to protect itself and its interests in that area? If Washington blockades Nicaragua or uses air strikes (usually called ''surgical'' in such circumstances) to prevent or remove ''offensive'' weapons from Nicaragua, it will incur the disapproval of virtually all its friends and allies. The loss in world opinion could outweigh the gain.
The Soviets have no scruples in such matters. They have never hesitated to use their armed forces to impose obedience and ideological conformity on their neighbors in Eastern Europe. But does Washington need to emulate the Soviets in order to protect itself?
Originally Washington's only demand on Nicaragua was that it cease sending arms to the rebels in El Salvador. Matters have now gone well beyond that stage.
In later exchanges the US has demanded as further conditions for a return to normal relations between the two countries that Nicaragua cease receiving Soviet weapons, reduce its armed forces to fewer than 20,000, adopt political pluralism (democracy) and a mixed economy, and commit itself to nonalignment.
The essential condition is that Nicaragua not become another political or military base for the Soviets in Central America. One Cuba is all that President Reagan proposes to tolerate. But to members of the Nicaraguan government, Washington's conditions amount to a demand that they surrender independence. Obviously they have no intention of refusing further shipments of Soviet weapons. From their point of view they are getting ready to defend themselves as best they can from the invasion they think is coming. Over this last weekend US Secretary of Defense Caspar Weinberger applied the adjective ''offensive'' to the latest weapons arriving in Nicaragua from the Soviets. The new weapons are said to include combat helicopters, surface-to-air missiles, and sophisticated radio detection and directional equipment.
Some Pentagon officials say the new weapons are primarily ''defensive.'' There is no objective way of saying whether a particular weapon is offensive or defensive. Undoubtedly some of the new weapons could be used to take the offensive against the American-supported contras operating against Nicaragua from Honduras.
A resort to arms between the US and Nicaragua seems to be coming on fast. It could still be headed off by an agreement between Washington and Moscow. There is no sign yet of any such thing.