With all due respect, I think you are totally wrong. When I send a letter to someone, the government needs a warrant to obtain that letter. So, if I send a text message or iMessage or IM directly to someone. I expect the same level of privacy. What makes it so different? A private communication directed to a specific telephone number, username, or email account should be just as private as if I wrote a letter, put it in an envelope and mailed it to someone. Whether the information is carried by the USPS, or via the internet I have the same level of expectation of privacy. The government should have no right to intercept it without obtaining a warrant.
And, if a "hacker" (basically anybody other than the NSA, FBI, etc) does this, they are guilty of violating federal wiretapping and computer hacking laws. But, when any of the alphabet soup agencies does it, it's OK?