Only use cloud backup systems that use Pre-Internet Encryption (PIE) and say up front that they don’t have the ability to recover your files without your password. Everything else is just pretty much waiting for the world to see.
All the Feds have to do is contact the SysAdmin and he’ll give them backdoor access to the files on the server. It would be a little harder for the hackers though. Of course if the hacker gets root access it’s game over.
And only deal with firms that keep their PIE-holes closed ....
Unless your name is Lois Lerner. </s>