WASHINGTON -- Forget the rules of the Secret Service or the U.S. Marines; it is really what the mothers of those men would have advised that would have saved them from the embarrassment, humiliation and ridicule (not to speak of unemployment) they have encountered after last week in Cartagena, Colombia.

Yes, once again, we must stop to consider the kitchen wisdom that "Mother knows best."

Take the venue. Mother is told that her Secret Service son is going to Cartagena to protect our president when he arrives there for the Summit of the Americas. And, wow, is she proud of that! Yet, she's worried about it, too. Mom, you see, is something of a lover of history, and she once read an article in Holiday magazine about Cartagena.

She found that the storied city, which is gorgeous, was founded in 1533, but throughout the 16th century fulfilled a strange historical mandate. It was at that time that the Spanish Conquistadores in Peru, down the Andes from Colombia, were stealing the exquisite gold pieces of the Incas. The Spaniards would send the gold to Cartagena, where they would be melted down into bars and then transported to Spain to pay for Spain's wars, along with slaves for the Spanish Crown.

This history bothered Mom, who was a Methodist Sunday School teacher. She told her son that nothing good could come from a city with so evil a soul, and she advised him to go only if the president himself insisted upon it.

Well, that turned out to be the case, so she fell back on her basic good advice: Don't drink, and stay away from the local women.

It seems clear from the recitation of what did happen inside the "forward group," called "junk teams" -- including Marine dog handlers, at least one Green Beret, Air Force and Navy explosive specialists, and some 20 Secret Servicemen -- that all of Mother's good advice was ignored.

As soon as their limited duties were finished at the Hotel El Caribe, quite a nice place, the men hightailed it to tourist spots like the Pleyclub, a bordello popular with Americans, where a bottle of Old Parr whiskey costs $160 and girls, cutely named Daisy, Lady and Paola, about twice that much. It was after a night of drinking that it was time to go home -- together, of course.

Now, our men may not have known that the hotel had very unforgiving rules about this.

Prostitution is legal in Colombia, but in what are called "tolerance zones." For good hotels like the El Caribe, prostitutes had to be "in" before 11 and "out" before 7. Actually, Mother would have scoffed at such an idea -- that the "hours" would mean that innocent tourists would not have to actually see the girls going in and out.

But this time, with the summit about to start and the president of the United States about to arrive, there was not only plenty to see, there was more than plenty to hear! It was then that some of the Americanos broke one of their mothers' most inflexible rules.

"Always pay your bills," Mother said. She said it when they were boys and when they were men. She realized how important it was not to beg trouble by creating bad feelings over money, especially with strangers. Which is just exactly what the men did!

When it was time to go, the girls demanded their money. One said it was $800 -- they weren't prostitutes, after all, they were from escort services. The men got loud and nasty, and offered $30. They threw the girls out. Latin American walls are thin. Everybody can hear everything. The girls helped that along by banging on the Americanos' doors, the police came, the hotel officers closed in -- and the secrets were out in Washington even before Bogota knew.

If the men had paid, and if they had just smuggled the girls out before 7 a.m., probably no one would have known! Such is life. Mother knew it, but her sons clearly did not.

Mother knew, too, that people are always far, far more interested in scandals with American service men than they are in summits, where they talk endlessly about the Cuban embargo and Colombian drugs, and are much more engaged by stories about free sex than free trade.

In the end, it was the Secret Service men and their pals who got all the ink. It was difficult to find an article on the American president trying to better relations with Latin America in any newspaper. All the space was given over to the hooker scandal. So, what the men really accomplished was to (1) upstage their president in the world press, and (2) provide the Latins with the idea that this was how Americanos behaved, even on a presidential tour.

Answering to Mother when they get home may turn out to be worse than answering to the White House.