For you Trumpers...Words matter. Now the word of the day is "spy." It used to be "snitch." The problem with those words to try and discredit someone is that they don't go to credibility! No one ever claims a snitch is lying, just being disloyal. A spy has info no one else can get--they aren't lying, just being disloyal. There is a word for people not telling the truth, they are called "liars." Unfortunately for the "Liar-in-Chief," the snitches and spies are telling the truth.
This does seem to be the main complaint... someone has revealed Trump's dealings, not that the dealings themselves didn't happen. He's since gone on to proclaim he has the right to ask foreign heads of state to tryi to dig up dirt on his domestic rivals and their families.
Imagine the screams of horror if a Democrat were to ask another nation to investigate Trump's real estate deals in that country. They'd be outraged. (And in fact this is happening- they're pissed that Congress is questioning his deals on the Russian Trump hotels...) So it's okay for Trump, but not for the other side. Just like in religion, what is done by our side is different from the same thing done by another.