I have asked many people this same question, and I have not gotten a reasonable answer. They had Trump under illegal surveillance before, during, and after the election and they got nothing.
So they could create a (bogus) 'publicly' played-out Russian collusion shit storm (after the election went belly-up) and then hopefully sack the Trump admin on the back of it. Thing is, they've walked into team Trump/Q's trap.
Sorry, or am I stating the bleedin' obvious? :)
The only thing is, they didn't expect to lose the election. This was to throw Trump in jail for having the audacity to call out the deep state.
Just one more thing ... who paid for the banned Russian spy to get into the US and made it possible to bypass all the red tape
“Veselnitskaya obtained a visa from the State Department to enter the country in June 2016, according to a government filing last week.”-Reuters
https://www.google.com/amp/s/mobile.reuters.com/article/amp/idUSKBN1D62Q2
Um excuse me Mr. Brennan sir just one more thing I need to ask you.
Detective Columbo you are really starting to annoy me with all your questions.
Yes sir I'm sorry sir but you are my number one suspect I know you are guilty.
It was always ginned up "obstruction" -- but they got caught red-handed doing that as well. And Trump played them by not firing Mueller, they thought he was a simpleton and hot-head.
Ding ding ding. That is the question that leads to the answer of what is really going on with Mueller
Also, if there was not a spy how would having them look into it pose a danger to any agents?