With speculation hot among the president's legal team that today could be a day for action by Bob Mueller (last working day before Labor Day), remember all the evidence the special counsel has — or could have — that we haven't seen.

Why it matters, from Bob Bauer, former White House counsel to President Obama, and now an NYU Law professor: "Investigators have the skills and resources to turn up evidence, including witness testimony, that goes beyond what anyone on the outside can imagine in the daily speculation about the Mueller probe."

"How many had heard of George Papadopoulos — until the day we heard of George Papadopoulos?"

"Who would have predicted an indictment, like the one brought against Russian intelligence officials, that reads like the synopsis of a le Carré novel?"

The evidence we've yet to see: