Last week marked the 10th anniversary of Portugal's ''Revolution of the Flowers,'' so-called because it brought about a peaceful transition from authoritarianism to democracy. The symbol of this revolution was not a bloody street fight, but lighthearted teen-agers who put carnations in the gun barrels of soldiers who seized power from Dr. Marcello Caetano. Those were days when the Portuguese people were filled with optimism; but a decade later, the ''Revolution of the Flowers'' is in danger of wilting on the vine.
For Americans, Portugal is a little country next to Spain, a place where warm sun hovers over whitewashed cottages. Portugal is the poorest West European country, far less developed and technically advanced than its larger Iberian neighbor. But Lisbon was also a founding member of NATO, and its continuing close ties with the United States are exemplified by the fact that one of America's most strategic military bases is located in the Portuguese Azores.
Unlike some of its north European allies, Portugal is not plagued by divisions over foreign policy. Except for the Communist Party, Portugal's political parties generally are agreed on Lisbon's firmly pro-NATO stance.
The major preoccupation of Socialist Premier Mario Soares is the battered economy, which never quite recovered from the dislocation caused by the revolution. Agriculture, for instance, remains the intractable problem it has been for a long succession of Lisbon governments.
Other economic news is not heartening. Portugal's foreign-trade debt has doubled; inflation hovers around 20 percent. Even Portugal's $10 billion gold reserve has failed to assuage fears among Western bankers that the country may not be able to meet its debt obligations.
What to do about the economic crisis is, of course, a matter of dispute among the Portuguese parties. This highlights the country's second major problem, which is the inability of a bitterly divided parliamentary democracy to ensure the development of a nation that in some respects resembles the third world more than its prosperous European neighbors. Lisbon already has seen the parliamentary shuffle of 15 successive governments -- with Soares now in his second effort to govern his people.
President Antonio Eanes is said to be disgusted by the spectacle of such revolving-door governments, and the popular President is thinking about forming his own political party. Unlike the French Constitution, which gives the president strong powers, or the West German Constitution, where the leader of the parliamentary majority is vested with executive power, the Portuguese Constitution does not make clear the delineation between presidential and parliamentary power.
All of this has given democracy a bad name in Lisbon. ''People must understand that one cannot merely improvise a democratic tradition -- it takes time -- and of course, we need the understanding of our American and European friends,'' Soares told me several years ago.
But, as so often happens in this country, concern about a foreign country's fate is directly proportional to the possibility of a Communist takeover. Now that Portugal is governed by the reassuringly moderate, pro-Western Soares, Lisbon is the object of relatively little Western concern. This was not always the case; for a time in the mid-1970s Portugal was on the lips of White House counselors and geopolitical strategists. US help for Portugal's democratic emergence, along with that of neighboring Spain, is one of the unsung achievements of the Carter administration.
On a more hopeful note, the hitherto lackadaisical US approach to Portugal's problems may have been ended by the visit of Mr. Soares to Washington last month. The Portuguese leader rang several alarm bells in the Reagan administration, which has decided to offer Lisbon $70 million in military credits, $55 million in guaranteed credits for military purchases, and $80 million in economic aid for fiscal 1985. In return, the Portuguese have given the US permission to use the Azores base for another seven years and also have given Washington land for the construction of an important satellite-tracking station in the Algarve.
It is anyone's guess whether Washington's aid, combined with other help from western European allies, will stem the tide of further Portuguese disillusionment with the ''Revolution of the Flowers.'' What is certain is that the aid came not a moment too soon.