Jurisdiction?
Suppose you went to Amsterdam, what would you likely see on sale? Illicit drugs perhaps? Sexual escapades? Certainly, you would find a great number of entertainments that are prohibitted here in the United States, but are completely legal and available within the confines of Amsterdam.

Question: Should the US Customs (or any US authority) have jurisdiction over US citizens who travel to other countries to partake in "regional" entertainments? Suppose you were to premeditate your vacation to Amsterdam for the express purpose of taking illicit drugs and contracting the services of a prostitute? Should the US government have the authority to both stop and arrest you on the premise that you had "criminal" intent?

Basis: An elderly man plans a trip to the Philippines as a "sex tourist." The US Customs Service detains him for questioning. Although the PE article is a bit vague, it appears the man is put on trial. Details seem to point to the fact that he had been in contact with a family in the Philippines to arrange acts of "underage" sex. While it is distasteful and illegal by American standards, if it is both culturally and legally accepted in the Philippines, what jurisdiction does, or should the US government have?