Pedophiles, Technology and the Constitution

Here's an interesting piece on how Interpol managed to un-photoshop images of a suspected child molester. As with having cracked Enigma in WWII, there's always a balance to be struck between keeping your knowledge of the enemy's secrets unknown to that enemy, and making use of the intelligence. Here, presumably they used every method they could to find the suspect without giving away their technological edge, but eventually had to place the welfare of the children he's continuing to harm ahead of the risk of alerting other criminals to their method.

The interesting constitutional issue is that from what I've read the man has committed most, if not all, of his abuses in Vietnam and Cambodia. So far as I know, traveling for the purpose of sexually abusing children abroad is the only U.S. federal crime that allows domestic prosecution for attempting to commit conduct that may or not be a crime where the act is committed and has no direct effects in the U.S. By contrast, I can't be arrested in the U.S. for traveling from JFK to AMS for purposes of smoking marijuana in Amsterdam.