Gen. Mark A. Milley has weighed in for the first time on a new book saying he went to extraordinary lengths to allay Chinese concerns about a potential military confrontation sparked by President Donald Trump.

The chairman of the Joint Chiefs of Staff told the Associated Press the calls were, in fact, “routine” and were meant “to reassure both allies and adversaries in this case in order to ensure strategic stability.” But he declined to expand on that, saying that would have to wait for his upcoming testimony on Sept. 28.

“I’ll go into any level of detail Congress wants to go into in a couple of weeks,” Milley said.

That testimony looms increasingly large, as multiple developments in recent months have detailed Milley’s reservations about Trump’s stewardship of the country. Combined with Milley’s public comments, they have turned a man in an important role, but who isn’t usually publicly well-known, into a lightning rod.

Even those critical of Trump have suggested Milley’s actions — the book from The Washington Post’s Bob Woodward and Robert Costa reports Milley also told China he would “call you ahead of time” if an attack was coming — say the episode raises troubling questions about military interference with civilian control. Others worry his actions and comments could politicize the military, as The Post’s Missy Ryan reported Friday.

On top of that report, another book by Post reporters Carol D. Leonnig and Philip Rucker this summer quoted Milley as drawing parallels between Trump’s effort to overturn the 2020 election and the rise of Adolf Hitler in Germany. Before that, he was targeted by prominent figures on the right for expressing interest in understanding critical race theory, and he apologized last year for appearing in a photo op with Trump after law enforcement used force to clear Lafayette Square outside the White House of racial justice protesters.

The latest report is certainly the biggest one, though, and it has cast a spotlight on Milley like never before — with plenty of details yet to be filled in. With that in mind, here are some big questions about Milley’s testimony Sept. 28.

1. How specific were his assurances — and what was the context?

Whenever there’s a major, complicated controversy like this, it can fall victim to oversimplification. Some have characterized Milley as simply downplaying the possibility of a U.S. strike.

But the report goes further than that, as The Post’s editorial board emphasized this week:

What could be considerably less benign is the pledge Gen. Milley reportedly made to alert Gen. Li Zuocheng ahead of any U.S. strike: “If we’re going to attack, I’m going to call you ahead of time. It’s not going to be a surprise.” According to “Peril,” this came in the Oct. 30 call — before the insurrection and, indeed, before the election. We struggle to understand what circumstances — absent clear authorization from civilian policymakers — could justify offering a foreign adversary such a pledge.

There are conflicting conceptions of precisely how rogue Milley was going. Axios has reported that reassuring China was Defense Secretary Mark T. Esper’s policy, and Fox News’s Jennifer Griffin has reported that many were looped into Milley’s calls.

Axios has also cited a source familiar with Milley’s calls as suggesting the message was less that he would tip China off and more that there wouldn’t be a surprise attack — perhaps because Milley viewed it as being illegal.

This is really the comment that everything hinges upon. Milley’s explanation of it is more or less the ballgame. And even if others were clued in, the circumstances of that promise will determine whatever becomes of this.

2. Why the need to reassure China?

While there are valid questions about Milley’s actions, others point to just why he was put in such a position in the first place. Trump has a demonstrated history of pushing and overstepping boundaries and norms, which frequently tested those around him when it came to their complicity or efforts to keep him in check.

But when the new report landed, the big question was: Why China? While there was certainly concern that Trump might do something drastic as he was headed out the door — given his drastic efforts to stay in office — there was no real indication it might pertain to China. Trump had used China as a political foil and launched a trade war with it, but there was little in the public record pointing to a brewing confrontation.

Axios’s Jonathan Swan reported that it appeared to involve faulty intelligence China was receiving about a potential confrontation:

In mid-October 2020, top Pentagon officials grew concerned about intelligence they’d seen. It showed the Chinese were consuming their own intelligence that had made them concerned about the possibility of a surprise U.S. strike against China, three sources familiar with the situation tell Axios.
...
Then-Defense Secretary Mark Esper worried the Chinese were misreading the situation and that their misperception could lead to a conflict nobody wanted.
Esper directed his policy office to issue a backchannel message to the Chinese to reassure them the U.S. had no intention of seeking a military confrontation. The message: Don't over-read what you're seeing in Washington; we have no intention to attack; and let's keep lines of communication open.

What that wouldn’t really explain, though, is why Milley was reportedly so concerned about Trump specifically — rather than the bad intel the Chinese were consuming.

Given Milley’s pledge to “go into any level of detail Congress wants,” he would seemingly be prepared to discuss all of this at-length — at which point people can better evaluate the appropriateness of his actions.

3. How can situations like this be avoided?

However you slice it and however many people were involved in what Milley was saying, the fact remains that this was an all-too-familiar type of scenario during the Trump administration. Numerous figures, including military leaders like former defense secretary Jim Mattis, described similar concerns about Trump, but they spoke out only after they no longer worked for him.

They have often explained that they felt they could do more good when it came to Trump’s unwieldy impulses by staying in office. This often required silence, a delicate dance and plenty of humoring, because they worried about being replaced by someone who would be more compliant.

But for all Democrats have said about Trump’s norm-busting and pushing of boundaries, they have demonstrated precious little initiative in changing the way government operates in response. Congress has over the last several decades ceded plenty of power to the chief executive to do things it struggles to do or doesn’t want to do. You’d think it would discuss what mechanisms could be used to deal with what happens when that gets exploited.

Just because you worry about the commander in chief, of course, doesn’t mean you have the right to undermine him or set up parallel diplomacy. That could create an awful precedent.

But if there’s anything that would seem to provide a crystallizing moment for potential reforms — especially given the prospect that the former president involved could soon seek a return to office — it would seem to be this. And Democrats (and Republicans alike, to the extent they have worried about Trump themselves) would be well-served to probe these kinds of questions. That effort very much starts with whether a president has too much power to launch military attacks, and what can be done when one oversteps even the limited obstacles in their way.