Two of the biggest stories in Washington right now are on track to collide in spectacular fashion. And it’s not clear — at least to me — that the political world is taking this possibility seriously enough, let alone prepared to deal with the fallout for our political system that might result from it.

Simply put: The battle over whether President Trump will sit for an interview with special counsel Robert S. Mueller III could end up running headlong into the confirmation fight over Trump’s Supreme Court nominee, Brett Kavanaugh, that’s set for this fall.

The Post reports that Rudy Giuliani, who is supposedly Trump’s lawyer, is preparing a letter to Mueller that will largely reject the special counsel’s latest suggested terms for an interview. Giuliani claims Trump’s team has “real reluctance” about Trump facing any questions about potential obstruction of justice. While it’s very possible something will be worked out, it’s also possible that, in the end, Trump may decide against sitting for an interview.

Giuliani has said that this decision will be coming in a week to 10 days, which means this could be upon us before we know it.

If Trump declines an interview, Mueller will probably hit him with a subpoena to appear before the grand jury, as he has privately threatened to do. But on ABC’s “This Week,” another Trump lawyer, Jay Sekulow, flatly stated that if this happened, Trump’s team will fight it all the way to the top.

“It would go to the Supreme Court,” Sekulow said, adding that “a subpoena for live testimony has never been tested in court as to a president of the United States.” Translation: If Trump decides against a Mueller interview, we are going to test this.

What this means is that, in advance of Kavanaugh’s hearing, we may already know that Kavanaugh could end up being the deciding vote on the question of whether a president (Trump) can be compelled to testify to a grand jury. Now, it is possible that the current court could rule on such a matter sooner (the eight justices might deadlock, defaulting to a lower court). But it’s also perfectly plausible, depending on how long Trump’s team takes to make a decision and what happens in the courts afterward, that this could be headed for a showdown in front of a high court with Kavanaugh on it.

Kavanaugh’s expansive views of executive power and privilege have been widely debated. Kavanaugh argued in 2009 that “we should not burden a sitting president” with “criminal investigations.” Kavanaugh’s suggested remedy was Congress passing a law to preclude this, so he doesn’t necessarily think presidents are constitutionally protected from such probes. He has said that the decision forcing Richard Nixon to turn over the Watergate tapes might have been “wrongly decided,” but he has also hailed it as a great moment in judicial history, in which the courts “were not cowed and enforced the law.”

We don’t really know for sure what Kavanaugh believes on these matters. But Democrats and liberal groups such as the Center for American Progress have suggested Trump may have picked him precisely because of his possible tendency toward deferring to executive privilege, which they have argued is grounds for him to recuse himself from any decisions involving Trump and the Mueller probe.

If we learn that Trump is being subpoenaed for an interview against his will, this would suddenly invest the question of what Kavanaugh really believes on these issues — and whether Kavanaugh will recuse himself — with practical urgency and immediacy. We will know before Kavanaugh’s hearing that he may soon be ruling on such a matter — in particular, the question of whether Trump can be compelled to testify.

Democrats from Trump states, such as Joe Donnelly, are remaining noncommittal on Kavanaugh pending their customary sit-down meeting with him. But if the above scenario starts to develop, they will — and should — face added pressure to drill down on these matters in their face-to-face interviews.

“Sekulow’s comments make clear that the question of whether a sitting president must be responsive to a subpoena may not be a hypothetical for very much longer,” Brian Fallon, executive director of Demand Justice, which is leading the fight against Kavanaugh, told me. “Kavanaugh owes his appointment to the man who may soon be a party in a case coming before the Supreme Court. Plus Kavanaugh has already expressed strong views on whether a sitting president should be able to be ensnared in criminal proceedings.”

“If this showdown materializes in the middle of the confirmation battle, it will catapult Kavanaugh’s expansive views on presidential power to the front burner,” Fallon continued. “At the very least, Kavanaugh ought to be forced to commit to recusing himself from any matter arising out of Mueller’s probe.”

It is unlikely that Kavanaugh will pledge to recuse himself during his hearing. It is also likely that he will try to avoid offering sufficient insight into his views of executive privilege to gauge how he might rule on a Mueller subpoena or any other Mueller-related matter, such as whether a president can pardon himself or his cronies or shut down a Justice Department investigation into himself, which the president’s lawyers claim he has the power to do.

The nightmare scenario

So we may soon face a situation in which a president whose campaign is under investigation for collaboration with a hostile foreign power’s sabotaging of our democracy — and who has gone to enormous lengths to both scuttle that investigation and to publicly vindicate that foreign power — is seeking to avoid questioning on these matters, with the help of the justice he just appointed, possibly (given what we know about Trump) in part for this very reason.

Trump, of course, has every right to appeal this to the court. And there are reasons that nominees don’t comment directly on matters they may be ruling upon. It should also be noted that even if Trump avoids a Mueller interview, this would not mean he is in the clear legally. But Trump is probably more legally vulnerable if he does the interview, and in any case, there is a strong public interest in Trump facing such questioning.

And if Kavanaugh does not pledge recusal or shed sufficient light on his views, senators are not obliged to confirm him. Indeed, you’d think this would present them with what should be a very difficult situation. It should become harder for any self-respecting red-state Democrat to support him. Heck, this scenario might even get a bit uncomfortable for vulnerable Republicans, since they are facing midterm elections that will likely turn heavily on voters’ desire for a check on an out-of-control president.

To be clear, there are plenty of ways in which this scenario might be avoided. But it is a possibility. And it is one whose outcome is not likely to reflect particularly well on our institutions.