A casual encounter the other day with George McGovern, in good humor and looking fit, set me thinking back to the start of his 1972 presidential candidacy in a convention hall in Miami. At 3 a.m. (prime time in Guam, it was noted), McGovern looked weary and sounded wearier as he accepted the Democratic presidential nomination with a limp appeal: "Come home, America."

It was easy to write it off to the "Vietnam syndrome" or to joke that it had the ring of a man on his kitchen stoop, calling his dog. And yet today, with all that is said about the resurgence of American confidence as a world power, it has the ring of prophecy. A good case can be made in hindsight that McGovern was playing not just to a malaise of the moment but to what has historically been (with notable exceptions) our natural inclination: to retrench abroad under the pressure of domestic imperatives.

If you doubt the strength of the underlying inclination, look and listen. First, listen to the president arguing for aid to the Nicaraguan contras. He lambasts the Democrats and vows that the Republicans will "stand a lonely vigil to guard the gates of freedom" -- at least until the November congressional elections.

Then, he said, the electorate would have a choice between a "weak, isolationist America in a world held hostage by pro-Soviet tyrants and Third World despots, or a strong, secure America that accepts its destiny as leader of the free world."

Now that is Reagan being Reagan, as his sometimes disenchanted supporters at the Heritage Foundation recently put it. A recent issue of the foundation's "National Security Record" finds the president finally standing up for the sort of things he stood for when he ran for the office in 1980.

What seems to escape the notice of the Heritage people is that Congress has already brought the Reagan defense buildup to a grinding halt.

Listen now to Secretary of State George Shultz, bending his every effort to rescue the U.S. economic and military aid program, including critical funds to fortify U.S. embassies and consulates against terrorism, from "devastating" congressional cutbacks. "What is being perpetrated here is a tragedy for U.S. national security," says Shultz, warning of the prospect of the United States' "withdrawing from the world."

The secretary isn't kidding, even when some allowance is made for what is obviously high-pitched sales talk. And the problem isn't new. U.S. presidents from Eisenhower and Kennedy down through the years have never had an easy time winning congressional support for foreign aid to the Third World; that kind of aid program has never had much of a constituency.

But past presidents have not been caught up in a Gramm-Rudman-Hollings fiscal winding sheet -- with a foreign-aid program that offers almost no wriggle room. Of the nearly $13 billion earmarked for the 10 biggest recipients (the bulk of the foreign-aid expenditures), almost half goes to Israel and Egypt; Israel is politically untouchable and so, under the agreement accompanying the Camp David Accords, is Egypt.

Four of the top 10 (Turkey, Greece, Spain and Portugal) are NATO partners; strategic military bases are involved. Subic Bay and Clark Field in the Philippines are said to be strategically irreplaceable. Pakistan is a crucial conduit for aid to the Afghan rebels. Honduras and El Salvador are critical for Central American policy. So the issue Ronald Reagan would pose before the electorate is nowhere near as simple as he would have us believe. Congressional leaders see it as a choice between foreign aid and domestic welfare. But Shultz points out that only two percent of the federal budget goes to "all activities directly in support of our foreign policy." The real issue, State Department people rightly argue, comes down to a balancing of security priorities.

Any significant reduction of the U.S. presence and influence in such countries as Turkey and the Philippines almost instantly raises the issue of military bases. That, in turn, throws the really hard choice -- the balancing of risks and the reordering of security priorities -- back to the administration.

It is not easy, for example, to imagine how a "strong, secure America" can fulfill its "destiny as leader of the free world" with a 600-ship Navy sailing around with no place to park for refueling, refitting and R&R for the crew. Nor is money everything: the U.S. capacity to influence events in the Persian Gulf is hardly improved when huge majorities of both houses of Congress vote down an arms sale to a country as central to U.S. strategic planning in that part of the world as Saudi Arabia.

There is more than one way for America to "come home" -- by conscious, careful design or by the collapse of a budgetary strategy that refuses to take into account that the money isn't there to pay for Reagan being Reagan. When you are confronting the real possibility of shutting down U.S. diplomatic facilities abroad for lack of adequate security, or of losing decisive leverage in furtherance of administration policies in such places as the Philippines and Pakistan, George Shultz's grim forebodings do not look far-fetched.