If we're essentially saying that it was only okay for the US and our allies to, for example, break the German or Japanese codes during WWII simply because Americans weren't also using the same codes, and therefore that is the only reason that the government could be "trusted" to not misbehave or abuse its powers, then we have a serious problem on our hands.
We are not saying that at all. It was okay to crack those codes because it was part of an effort to fight a DECLARED war against a foreign power. Those ciphers were specifically being used protected the military communications of our enemies. (Yes I am aware Enigma had commercial applications) The message they were focused on cracking specifically were those where there was GOOD CAUSE to believe they military communications.
There is nothing wrong SIGINT or pretty much any and all efforts to obtain information related to an entity we have lawful declaration of war against. Its a grey area where it comes to foreign nations which we are not at war with.
Its a violation of the 4th amendment in the opinion of many reasonable educated American citizens when it comes to doing it to us. You have already demonstrated that you will play fast and loose with any restrictions placed upon you. The hole 3 steps linking meant practically everyone's records were subject to tap, for example. So the fact your ilk and you sir are ilk because your comparisons of our largely impotent (in real terms of ability to cause mass causalities or economic harm no self inflicted in response ) terrorist enemies of today to those of WWII which had massive armies on the march and sunk our naval fleet off Perl Harbor is a blatant attempt to create fear and distract from the real issues.
Society simply does not have a strong enough interest in the ability decipher most peoples private communicates. If you have enough evidence obtained by methods most of the public would agree is reasonable to actually obtain a warrant to track someones phone, or seize their computer, intercept their e-mails etc, you probably have near enought to convict anyway. The thing is you don't have that, instead you grab up people with your little dragnet and than parallel construct your way to an excuse to size something that you than have to decipher because you need that evidence as you can't talk about anything else. Never mind all the other folks whose rights your violated along the way, nope its all good because it puts criminals behind bars. Guess what our justice system was predicated on the idea of individual rights needed to be respected even if that means the guilty go undetected or get aquited perhaps even most of the time. The fact they YOU DON'T LOVE AMERICA AND FREEDOM to borrow and politically charged quote of the day isn't our problem.
100 years ago it was okay under the 5th amendment not to tell you where I'd buried my ledgers in the woods, so today should it be okay for me to use encryption that you don't know how to break and not give you the keys.
Do what you want to ISIS AFTER CONGRESS DECLARES WAR until then go sit in the corner quietly and masturbate or something.