Roger Stone and WikiLeaks

Mr. Mueller’s indictment of the Trump adviser Roger Stone alleges that Mr. Stone worked throughout the summer of 2016 to get in touch with WikiLeaks and became aware of the organization’s plans to disclose hacked information. Mr. Cohen claimed in his testimony to Congress that he was in the room when Mr. Stone informed Mr. Trump that WikiLeaks was planning a “massive dump of emails that would damage Hillary Clinton’s campaign.”

Was Mr. Stone coordinating with the campaign in his efforts to get information from WikiLeaks? How much did Mr. Trump know about what Mr. Stone had found out? And who in the campaign, if anyone, might have been aware of separate efforts by the Republican operative Peter Smith to obtain additional Clinton emails from sources Mr. Smith believed were Russian hackers?

Flynn’s Promises to Moscow

The national security adviser Michael Flynn was fired just 24 days into his tenure over fallout from his transition-period contacts with the Russian ambassador at the time, Sergey Kislyak — a matter about which he later pleaded guilty to lying to federal investigators. When he promised Mr. Kislyak that Mr. Trump would lift sanctions on Russia imposed by the departing Obama administration, was Mr. Flynn freelancing or was he acting on the instructions of someone higher?

Russian Influence Operations

Almost every case that Mr. Mueller has filed has illuminated a different facet of what appears to be a systematic, long-running effort by the government of Russia to reach out to Mr. Trump’s world. It’s clear that the Kremlin was attempting to gain access and influence. Was it also out-and-out working to recruit agents within the Trump Organization and campaign?

On our side of the Atlantic, to what extent was that outreach welcomed and reciprocated by the Trump team, and to what extent was Mr. Trump a passive beneficiary? Did the Trump Organization and campaign understand and respond to those instances as manifestations of a systematic effort by the Russian government or as unrelated connections with unconnected Russians?

Obstruction of Justice

Mr. Mueller has also reportedly conducted an investigation into potential obstruction of justice by the president: possible interference with the special counsel’s efforts , and with the F.B.I.’s before that.

Mr. Barr, among others, has argued that action authorized by the Constitution — like dismissing the F.B.I. director — by definition cannot constitute obstruction. Will the report sidestep these tricky legal questions by showing efforts by Mr. Trump to derail the inquiry that fall plainly outside the scope of presidential authority? To what extent does the obstruction investigation overlap with the collusion investigation — meaning that the special counsel and the F.B.I. understood the president’s apparent efforts at obstruction as part of the troubling pattern of coordination with the Russian government that incited the investigation in the first place?