Admitting that your son met with Russians who offered dirt on your opponent is not collusion.
If it were, Hillary’s campaign funded collusion by funding the Steele dossier, where Russians were *paid* to create dirt on Candidate Trump.
Yes, it’s collusion that he knew about, was informed of beforehand, during and after, and covered up.
The key point is that they were foreigners. Fusion GPS was a domestic contractor. It seems a technicality, but it’s significant.
The question is what laws were broken.