President Reagan is intent on sending an unmistakable signal to the Soviet Union and its surrogates with his decisions to stand firm in Lebanon and join an invasion of Grenada.

The message: After a decade of Vietnam-induced military paralysis, a U.S. administration again is willing to use the nation's armed forces when it deems American interests are threatened.

Moscow is put on notice that further Communist probing around the globe, which U.S. officials consider highly likely, involves increased hazards for Russia.
Soviet client states, such as Cuba, Nicaragua, Libya and Syria, also are put on notice that they can persist in mischief-making in Central America and the Middle East only at the risk of a direct confrontation with the U.S.

High stakes. In weighing his responses to the crises in Lebanon and Grenada, Reagan grappled with the most agonizing decisions of his Presidency. At stake were the risks of war and his prospects in a run for re-election.

In both cases, he chose a potentially high-risk option. The reason: He was convinced that he was dealing with two thrusts in an increasingly bold Soviet campaign to undermine the U.S. global position and expand Moscow's influence worldwide.

He saw the terrorist massacre of more than 225 servicemen in Beirut and the bloody coup by Marxist extremists on the Caribbean island as tests of American resolve to counter this campaign.

As he put it in an October 27 televised address to the nation: "The events in Lebanon and Grenada, though oceans apart, are closely related. Not only has Moscow assisted and encouraged violence in both countries, but it provides direct support through a network of surrogates and terrorists."

In Lebanon, administration officials maintain that the failure of Reagan to hang tough in the aftermath of the slaughter of the Marines could have undermined America's credibility as a superpower.

"If we are driven out of Lebanon," said Secretary of State George Shultz, "the message will be sent that relying on the Soviet Union pays off and that relying on the United States is fatal."

In Grenada, the White House sees the Communist challenge as even more direct in light of the discovery there of huge stockpiles of weapons, ammunition and military equipment. The island, Reagan declared, "was a Soviet-Cuban colony being readied as a major military bastion to export terror and undermine democracies. We got there just in time."

It was the fear of such a development that prompted members of the Organization of Eastern Caribbean States to enlist help from the Reagan administration for a military move against the radical Marxists who killed Grenada's top leaders on October 19, after a bloody coup on October 12.

For the President, the time for agonizing decisions is far from over. Tough choices still lie ahead as he deals with the repercussions of events in Lebanon and Grenada and the implications of his actions at these flashpoints.

At home, his challenge is to demonstrate convincingly that he is not leading the nation into a disastrous quagmire in Lebanon and that his growing reliance on military power is warranted and effective.

Abroad, he must cope with a new crisis of confidence among America's friends and allies, triggered by almost universal denunciation of the operation against Grenada.

The invasion of the Caribbean island-popular as it may be in the U.S.has isolated Washington internationally, even from its closest allies in London, Bonn and Rome. Britain's Prime Minister Margaret Thatcher, whom Reagan consulted shortly before the troops landed, tried unsuccessfully to persuade him to call off the operation.
Lone vote. The extent of American isolation was dramatized in the U.N. Security Council on October 28. The U.S. found itself alone in voting against-and thereby vetoing-a draft resolution deploring the invasion of Grenada and calling for an immediate withdrawal of foreign troops.

Allied officials in Europe complain that the U.S. has lost the moral high ground that it occupied as a result of the Soviet invasion of Afghanistan and more recently Russia's downing of a Korean airliner. For Reagan, all of this poses difficult new problems in pursuing major foreign-policy objectives.

Doubts overseas about the President's leadership and the legitimacy of the action against the tiny Caribbean island come at a crucial moment for the Western Alliance, with the approaching superpower showdown over deployment of medium-range nuclear missiles in Western Europe.

Among allied policymakers, the fear is that an anti-American backlash will strengthen the so-called peace movement that is campaigning to kill the missile plan.

The President's stand on Lebanon and Grenada also is bound to deepen the chill in U.S.-Soviet relations. The Russian media have branded the Grenada invasion an "act of undisguised banditry and international terrorism." The expectation is that Moscow will exploit the hostile reaction in Western Europe in a final effort to mobilize opposition against the U.S. position on Euromissiles.

And finally, the vociferous reaction in Latin America to the Grenada operation may complicate Reagan's efforts to gain the cooperation of the Contadora Group-Panama, Colombia, Venezuela and Mexico-in the search for a settlement of the Central America crisis.

Administration officials are confident that much of the damage overseas will prove transitory. They say that Europeans have reacted prematurely and will have second thoughts in view o1 evidence of the threat to the safety of 1,000 Americans in Grenada and the scale of the Cuban military buildup discovered on the island.
Bogging down? Far tougher for the President is the dilemma he still faces in Lebanon in the aftermath of the mass killing of Marines. He has made it clear that withdrawal of the American troops is out of the question as things stand now. While there is no widespread demand for early withdrawal of the Marines, the Beirut massacre has intensified a feeling on Capitol Hill that the U.S. is becoming bogged down in a hopeless mess in Lebanon.

This fear is fed by the increasing evidence that establishing an independent, unified Lebanon free of foreign armies is an impossible mission for the 6,000man multinational peacekeeping force with its 1,600 American Marines.

Any effort to expand the U.S. contingent, a move Reagan says he does not contemplate, would inevitably face strong opposition on Capitol Hill. The lawmakers only grudgingly agreed to maintain the existing symbolic military presence there for 18 months.

Reagan's dilemma is summed up by Senator Alan Cranston of California, a Democratic presidential candidate: "There is no clear way out. We cannot retreat under fire, and if we were to declare war, we wouldn't know who to declare war against."

In the absence of early progress toward reconciliation of the warring Lebanese factions, administration officials say that the leathernecks doubtless will suffer continuing casualties. They acknowledge that this is likely to generate new pressures across the country to withdraw the troops.

Political observers say that Reagan risks the same fate over Lebanon that befell former President Carter on the Iran hostages: Initial rallying around the President and then slow erosion of support that turns into swelling criticism.

Election factors. They say that Lebanon could emerge for Reagan as a major-and damaging-issue in the election campaign if there is a steady toll of leathernecks in a seemingly nowin situation.

By contrast, observers say that the Grenada venture could end up as a net plus politically for the President. Opinion polls indicate his October 27 address convinced an overwhelming majority of Americans that the invasion was justified to avert a possible repetition of the Iran hostage crisis and to stop Cuba's Fidel Castro.

The White House says that the response was virtually unprecedented, with 6,100 telephone calls supporting the President on Grenada as well as Lebanon and only 483 opposing him.

Most experts believe, however, that the ultimate political impact of the Grenada intervention will depend on whether the troops can withdraw quickly and whether the new government in Grenada turns out to be at least neutral if not friendly.

Actually, electoral factors seem to have played little part in Reagan's deliberations on how to deal with the crises in the Mideast and the Caribbean. Instead, his decisions reflect his conviction that Moscow is waging a dangerous global crusade against U.S. interests.

His primary aim is to demonstrate his resolve to respond to this challenge-when necessary with military power-whatever the political consequences at home.