I’m not trying to make a political point here, instead merely offering this as info for travelers coming into the US. If you’re traveling into the US (citizen or non-citizen) be aware that your laptop, mobile phone, mp3 player, or any gadget “capable of any device capable of storing information in digital or analog form” may be taken for inspection by the TSA. This also includes video, video tapes, books, pamphlets and “written materials commonly referred to as pocket trash or litter.” This practice by the USA’s Transportation Safety Administration has actually been in effect for awhile but now the Department of Homeland Security is actually acknowledging it publicly.
This, like everything since 9/11 is draped in the cloak of national security. Once your gear has been impounded it can be kept for a reasonable period of time. There are reports of this taking quite some time in some instances. Note that this can occur without any suspicion of wrongdoing on your part and that officials may share copies of your data with other agencies.