[NeroASERCH]

But that's just it. Who's interest, if anyone's is actually being served? We submit to governance under the belief that government will enforce the law with only sufficient force to do its job and no more and the 4th ammendment (and by implication the power of the state is limited under the 3rd ammendment as well) actually stand for something, not merely for something convenient. If it is convenient and therefore defacto legal to search people on Federal property because it's convenient (which under Federal law only restricts access specifically with notification not generally) then it's easily extensible to search people on any property at any time for any reason. In other words if the law does not restrict the government because it's just easy to do whatever proscriptions are in the law then the 4th ammendment really doesn't mean anything. The Federal government is supposed to have the burden to demonstrate that some public interest is served by this exception.

For example is there a difference between asking for that information and doing something with it? Can the government punch your SSN into a handheld device on the bus and record where you were and when? Can it check for bench warrants and supercede the local law enforcement powers? Can it simply use this as an intimidation on its face with the assumption that simple intimidation is itself a public good? These are fundamental questions that define the limits of liberty.