so, a way off hypothetical here, this likely isn't true.
But what if Mueller is building a case as he is not with the goal of entrapping Trump, but forcing his resignation? Mueller already has Manafort and Flynn in his pocket, and as such he likely has already more than enough to press serious charges on Don Jr. and Kushner. And Mueller is almost certainly looking at financial malfeasance within the Trump organization. Its still an open question as to what charges can be levied at Trump while he's President, but Mueller's investigation would be a lot less politically viable if Trump were to step down. The investigation wouldn't stop at once, but so far its scope has been limited only to peripheral characters within the campaign. It could well end with the fish they've already hooked.
Trump can still protect his family (which he, in theory still cares about), his fortune (or the perception of it), and even himself (say Pence gives him the Nixon treatment), all he has to do is quit.
Why would Mueller prefer or accept Trump's resignation to prosecuting Trump Jr. and Kushner if those two committed things blatantly more serious than what Manafort and Flynn were known, before this investigation, to have done that Mueller brought charges against them for? Robert Mueller's endgame isn't Trump or even anything to do with Russian interference in the election which is his commission. His endgame goal has always been prosecutions of any kind, that's the whole point.
Manafort got got for the same reason he had to leave the Trump campaign. Flynn got got for the same reason he had to leave as NSA. Neither one was related to the election, and Flynn's charge was only tied to the Russians in that's who he lied about that they agreed to him taking the hit on.
And none of this answers the question I keep having and have had of what exactly is supposed to be the accusation at the center of this? "Trump coordination with the Russians" is meaningless to me in the abstract. Especially since they apparently pulled it off so well that literally nobody else on the planet has discovered this in two years and that to uncover this whole thing Robert Mueller apparently needs Michael Flynn, someone guilty of providing false testimony to the FBI (and admitted to having provided false testimony and documentation to others including the Vice President), to testify to this giant secret that he's also managed to keep secret until now. So secret that not even his idiot son knows about it?
Neither Flynn nor Papadopoulous pled guilty to any overarching scheme or collusion or anything like that. Nobody has been charged for anything related to the campaign. There's no picture at all of what if anything is in the case Mueller is supposedly building that will shock the foundation of Trump's shoddy administration. So not only do we have the most successful secret criminal international conspiracy in history, we have the most successful secret investigation of it, in that neither one has like every other instance in history had even the slightest details exposed.
And just imagine, had Seth Rich not been killed, we would have known exactly all of this, well before the election.