I think it's fairly obvious that Trump has done something illegal in regards to Russia. He's gone out of his way to protect Michael Flynn and risk obstruction of justice charges over something he had no part of?
He was warned by first the Obama administration, and then later Sally Yates that Flynn may be compromised by Russia. Knowing this he chose to ignore the warnings, and instead fired Sally Yates. It was not until New York Times were about to go public with this information and gave the white house a heads up that he fired Flynn right before that story broke.
The very next day he invited James Comey over, and ordered everyone else to clear the room (despite Jeff Session's reportedly not wanting to leave at first, presumably because he thought it would be a bad idea) and then he reportedly told James Comey that "Flynn is a great guy." Asked for Comey's loyalty three times, and said "I hope you can see to letting this thing with Flynn go."
Just one day after firing Flynn for lying to Mike Pence and the FBI.
Then as you know, he fired James Comey (when he wouldn't let it go) and admitted on TV that he did so while thinking about the Russia investigation. Etc.
These things will likely come up in court if Trump is impeached. I don't see why he'd go out of his way to risk obstruction of justice charges multiple times if he's not involved. Add to the fact that he is hiding his tax returns, and there's definitely something he doesn't want people to see. It may just be money laundering or something, rather than collusion. But he's very much behaving like a guilty person.
Then we have the Trump tower meeting, where his son Don Jr already admitted to attempting to collude with a Russian official. His story is that they never got anything, and instead talked about adoption. Even if that's true, he went there with the intention of conspiring, which is enough. And in case his story about the abortion isn't true, Manafort may have something interesting to say about it.
As for Manafort would have agreed to cooperate already if he had something. That's possible, but it's not certain. Unlike Cohen who pleaded guilty, Manafort's approach was to plead not guilty. And on 10 of the 18 counts, the jury was indecisive. (Resulting in a mistrial on those counts.)
This trial could have ended with him being found not guilty on any count. And no matter how it ended, his lawyer could dispute the convictions. It seems like they won't though, because his lawyer thanked the judge for "being fair".
Let's assume Manafort has something on Trump and Trump knows it. The first course of action, if they believe they have a case for 'not guilty' would be to try that in court first. It's not a good look for Trump to pardon him all of a sudden, so that would be a last resort.
If that is the situation, then these convictions Manafort got may serve to provoke Trump to pardon him. Because now, Manafort is facing jail time. Possibly for the rest of his life. And most certainly, if he is found guilty of some of the upcoming charges. Now that jail time is not just a possibility, but a certainty, he'd be more inclined to coperate with the special council if he has something of value.
There's no reason to go over the history. Asking Comey not to pursue Flynn was inappropriate as far as norms and appearance of propriety ethics go, but is in keeping with Trump's general behavior. You assume criminal intent, but it's something he would do either way, so there's really no significance.
He's hiding his tax returns from the press, not the IRS. Why you think that would be significant to Russia, I don't know.
Don Jr. has never admitted to anything that would amount to collusion.
You can believe what you will about Manafort. I don't see him holding back and putting the rest of his life in the hands of a jury to protect Trump. Just not going to happen.
I'm not sure why you brought up Sally Yates being fired as her firing was for gross insubordination, and properly so. If she couldn't perform her role, she should have resigned instead of instructing her department to undermine the president's policies. If she had resigned, that would have been the honorable path and I would have respected it. And, ultimately, the travel restrictions that she ordered her department not to defend were upheld in court. Frankly, she has no business in government if she thinks she can set up her own policy directly contradicting her superiors and should be forever disqualified from public service.
Yes. Cohen pleaded guilty to tax fraud, false statements to a bank and campaign finance violations tied to his work for Trump.
There is no question any more if it was a campaign contribution. At least not in this case as it stands, because he agreed that it was and pleaded guilty to just that.
(If Trump stands trial, his legal team will no doubt contest it though.)
Keep in mind that Clinton was impeached just for lying about having sex with a woman in his office.
Trump has been implicated in federal crimes. That didn't even happen to Nixon.
Cohen choosing to plead guilty on that specific charge does not strengthen the legal theory that it's a campaign contribution. All it means is that Cohen chose not to challenge it as a part of the deal he made.
It's still a fairly weak legal theory. I wouldn't want to base a prosecution on it.