That was Angela Merkel's position, too!  She was cranky to discover that the US intelligence agencies were reading her mail and such.  

I think Germany is still an ally, but that didn't keep the Obama administration away from her private matters.

And every administration, including Trump's, will do the same.  

And we still have an Israeli spy in Federal custody for doing the same thing to us. 

"Henry L. Stimson was secretary of state in the Hoover administration. In 1929, he closed down the State’s cryptanalytic office because "gentlemen don't  read other people's mail".

 Fortunately he changed his mind when he headed the War Department under Franklin D. Roosevelt. Had the United States not broken the Japanese code in the early years of World War II, tens of thousands of American lives would have been lost. The same is true for the Brits intercepting German radio traffic with the now-famous Enigma machines at Bletchley Park."

 That is just the real world.