Furthermore, considering no one now thinks he colluded, it can be assumed Trump is innocent of this charge. If he is innocent, he would have known he was innocent, so why would he even bother to try and obstruct. It makes no sense.
While it's likely Trump did NOT personally collude with the Russians, that can't be said for members of the Trump campaign. And Flynn is just the tip of that spear...think of Kushner meeting with the head of a banned Russian bank, why? Think of the plan to use Russian intelligence facilities to talk with Russia, why? Why did Carter Page travel to Russia with the permission of the Trump campaign? Why, of all the potential countries to meet with was Russia the one country that so many Trump people met with and then forget to mention those meetings on their security forms?
Why, if nobody is guilty of collusion does everybody scurry around acting guilty?
As for why Trump would go out on a limb for Flynn and try to get him off, one wonders what Flynn may have to say about the campaign and it's activities. What would Flynn have to say that would be worth immunity?
Also, to be clear, of those entities investigating the Russians and possible collusion, as far as I know, nobody has actually said there's zero evidence of collusion...as far as I can recall they've been tight lipped because the investigation is on going. We won't really know if there's any evidence until the investigation is over...and now that Mueller is involved and his all star line up of investigators, if there is any evidence, they will find it.
I'm far more convinced Mueller will run an honest and exhaustive investigation and get to the truth. I can live with whatever they determine. If the Trump campaign didn't collude, they didn't collude and we can all move on. If they did, and anybody broke a law, they should pay for their crimes.
In any event, we need to learn EXACTY what Russia did, how they did it and figure out a way to absolutely prevent Russia or any other bad actor from interfering ever again. Can we at least all agree with that?