An alternative explanation is that they all know that they are as bad as each other..
Precisely.
When the president Nixon visited China back in 1972, there was a great deal made of the extreme lengths China was going through to absolutely insure his safety while there.
When the question came up on the news, I remember one of the big anchormen (Cronkite? or Brinkley?) asking the reporter on the scene how security arrangements were progressing. The reporter made some comment to the effect that both China's state security agencies and the US Secret Service were cooperating closely, and that arrangements were proceeding with an amazing degree of speed and efficiency. The reporter also said that the security people from both nations seemed to hitting it off extremely well on both the personal and professional level.
That prompted the anchorman to say something along the lines of how secret services seem to have much in common and act the same - no matter which flag they serve.
I think the same rule applies here. Government spies behave like government spies the world over. About the only thing that seems to differentiate the deeds they do in service to their masters is the size of budget given them, and the degree to which their masters are willing to turn a blind eye towards violations of law committed under the guise of national security.
We all know that.
But we can't really "prove" it.
The NSA, however, is in the enviable position of being able to provide
incontrovertible proof of exactly how - and to what degree - other nations are spying on their own citizens.
And
that is not the sort of laundry any government is anxious to see aired out in public.
There's an old saying that goes: "Let he who is without sin cast the first stone." And it's now being said again.
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