Your (and my, and any individual citizen's) personal interpretation of the Constitution is not the measure. It is the interpretation and implementation by our three branches of government.
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.--That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, --That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.
Government's job is to secure and protect the rights of the people. The government can decide/declare anything it wants, but if the overwhelming majority of people refuse to comply there is actually very little it can do, and it risks being abolished and replaced/restored.
So how about you consider the alternative: one where you don't assume that everyone working at every/any level of government, e.g., NSA, doesn't have the worst motivations and is actually trying to do their best to honorably, legally, and Constitutionally, protect our nation and its people instead of the opposite. How about that?
Sorry, but that boat sailed with all the lawlessness and abuses that have been revealed regarding domestic data/comm interception/storage, the widespread use of parallel construction, and the mass compromise of encryption schemes.
History proves over and over that the biggest danger to life and liberty is and has always been one's own government. The kind of "trust" you advocate for in this context would be foolish.