Where does the "physical access" part come from? And if that was the case, why would it be impossible now?
One of the sources: http://www.forbes.com/sites/erikkain/2013/12/30/the-nsa-repo...
One of the sources: http://www.forbes.com/sites/erikkain/2013/12/30/the-nsa-repo...
Basically how it worked was they jailbroke your iPhone and installed spyware on it. Is it quite likely that today, 7 years later, they have a remote 0day to do the same? Absolutely. But there's no proof that "the NSA has total control over all iPhones".