President Ronald Reagan never ceases to amaze. Not too long ago he was accused of being a part-time president. No workaholic, he. Then, in one week, he has shouldered a crisis in Lebanon, invaded Grenada, and fired three liberals from the U.S. Commission on Civil Rights. Not bad for a week's work.

Of course, there have been some casualties: 225 dead and 78 wounded in Beirut. There are at least eight Americans who died on an island in the Caribbean, 39 wounded and eight missing. Then there is another casualty: Call it trust or confidence in one's government. Regardless of political affiliation, most Americans have been spared during the past decade or so from the uncomfortable suspicion or conviction that their government was behaving like an outlaw in the community of nations. That's a rather open question again.

The invasion of Grenada, we are told by Dominican Prime Minister Eugenia Charles, wasn't really an invasion. In an interview with USA Today, she said: "It was an attempt by us to prevent trouble coming to our country." Grenada, she said, was helping dissidents in the Caribbean. Another nest of Marxist vipers near the bosom of democracy. Hence the multinational invasion in which only the Americans fought.

President Reagan's best case for the invasion was that some 1,000 Americans living and studying on the island were in grave danger of becoming hostages to a Marxist government that had come to power in a bloody coup. Unfortunately, this line of reasoning failed to persuade even as hard a hard-liner as British Prime Minister Margaret Thatcher. She, of all people, urged restraint--Grenada is a member of the British Commonwealth--and in a midnight phone call Sunday to Reagan asked him not to invade.

While Britain has not officially condemned the American action, most of our other allies have. The worldwide reaction to the invasion is hardly the stuff with which to inspire confidence in the American people that the administration took the best course. Former West German chancellor Willy Brandt, for example, made the point that America's high-minded condemnation of the Soviet invasion of Afghanistan now "loses credibility." It's an odious comparison, but it's also a telling one.

For military reasons, the administration acted in secrecy, without preparing the American people or getting their support. Americans woke up Tuesday morning--still reeling from the Beirut massacre that caused the heaviest loss of military lives since Vietnam--to find that their president had undertaken a military adventure on an island that sounds like it belongs near Spain. As the story unfolded, it didn't get any better. There were more Cubans on the island than the administration had thought, hence more American casualties. While medical students returned to the states and kissed the ground and thanked their saviours, just how much danger they were really in--as opposed to how much danger they thought they might be in--remains a huge question mark.

To make matters worse, the administration for the first two days kept all news reporters off the island so that the only information about what was going on was coming out of the Pentagon. Four reporters who had landed on the island in order to cover the invasion were removed by helicopter and taken to the USS Guam. The official explanation was that a military commander had decided their lives were in danger. The unofficial fact is that while the country was not officially at war, its people were being subjected to government-controlled news. In a word: censorship.

The book on the Grenadan invasion will remain open for some time. But it seems fairly clear that the administration did not try other methods of resolving its concerns with events in that country before taking rather drastic measures and doing so in secret. Eight Americans are dead who might still be alive, and 39 are wounded who might still be whole.

Betty Friedan, author of the "Feminine Mystique," and an outspoken critic of President Reagan, spoke last week of his "macho-cowboy" diplomacy. It was a nicely turned phrase, then. It seems rather appropriate, now.

President Reagan's hard-core supporters no doubt will be elated to know that the real Ronald Reagan has finally stood up. But to those less content with the notion that might makes right, the precipitous and secretive actions he took toward what at best was a perceived threat can only raise anxious questions about the way he would respond to a real one.