From a recent op-ed on MSNBC:

For most of our history prior to the 9/11 attacks, a fundamental American principle was that those who search, seize, intercept and detain should not be allowed to decide who are the bad guys because of political differences, vague suspicions, or incidental associations. The problem with widespread, intrusive surveillance is that the government treats ordinary Americans with suspicion, and it continues to massage the data until it is satisfied that there are no incriminating associations. What has become of the principal of presumption of innocence?

When our government suspects its own citizens we have lost the founding principles of liberty and equality.