For those that thing warrantless tapping a small price...

"...it is proper to take alarm at the first experiment on our liberties. We hold this prudent jealousy to be the first duty of Citizens, and one of the noblest characteristics of the late Revolution. The free men of America did not wait till usurped power had strengthened itself by exercise, and entangled the question in precedents. They saw all the consequences in the principle, and they avoided the consequences by denying the principle. We revere this lesson too much soon to forget it."

-James Madison, Memorial and Remonstrance Against Religious Assessments. Italics mine.