Next we start looking into their past associations. Or are we doing that already?

Not only are they spying on you without a warrant, but they're spying on your friends and family, too:

The F.B.I. cast a much wider net in its terrorism investigations than it has previously acknowledged by relying on telecommunications companies to analyze phone-call patterns of the associates of Americans who had come under suspicion, according to newly obtained bureau records.

The documents indicate that the Federal Bureau of Investigation used secret demands for records to obtain data not only on individuals it saw as targets but also details on their "community of interest" — the network of people that the target was in contact with. The bureau stopped the practice early this year in part because of broader questions raised about its aggressive use of the records demands, which are known as national security letters, officials said.

...

Typically, community of interest data might include an analysis of which people the targets called most frequently, how long they generally talked and at what times of day, sudden fluctuations in activity, geographic regions that were called, and other data, law enforcement and industry officials said.

The F.B.I. declined to say exactly what data had been turned over. It was limited to people and phone numbers "once removed" from the actual target of the national security letters, said a government official who spoke on condition of anonymity because of a continuing review by the Justice Department.

An FBI spokesman felt it "important to emphasize" that they're not doing this anymore, and another official said that community of interest requests "appeared to have been used in a relatively small percentage of the tens of thousand of the records requests each year."