What happens within the borders of a country is different, even if it is spying and suppression of human rights and what not.
The destiny of a country should be in the hands of it's people. Be it good, bad or worse. But if you allow propaganda from another country to enter into your media, all is lost. Why? Because you lose faith in everything. How is one sure the revolution in a country is pure bred from that country? How is one sure the change one sought is because of the needs of the people of that country?
It's an incredibly dangerous situation. Even if your own govt. spies on you, stopping the propaganda of a foreign country takes precedence at all costs, if necessary, even by war.