"In other words, if cell phone service providers were taking their customers' privacy (and constitutional rights) seriously, then this Supreme Court case should actually be the government suing a cell phone service provider for not turning over customer data in a case where a warrant has not been issued. "

As much as i hate the cell phone providers, they are fairly screwed here.

See, https://en.wikipedia.org/wiki/Communications_Assistance_for_...

and

https://en.wikipedia.org/wiki/Stored_Communications_Act

and friends.