Nick Pope pens perhaps the most interesting op-ed of the summer:
A healthy skepticism about extraterrestrial space travelers leads people to disregard U.F.O. sightings without a moment’s thought. But in the United States, this translates into overdependence on radar data and indifference to all kinds of unidentified aircraft — a weakness that could be exploited by terrorists or anyone seeking to engage in espionage against the United States.
The American government has not investigated U.F.O. sightings since 1969, when the Air Force ended Project Blue Book, an effort to scientifically analyze all sightings to see if any posed a threat to national security. Britain and France, in contrast, continue to investigate U.F.O. sightings, because of concerns that some sightings might be attributable to foreign military aircraft breaching their airspace, or to foreign space-based systems of interest to the intelligence community.
See here for a critique of a paper attempting to explain why there is a aversion to consider UFOs as the result of “the functional imperatives of anthropocentric sovereignty.”