Marine Corps Gen. James Mattis listens during his confirmation hearing July 27, 2010 on Capitol Hill in Washington, DC. Alex Wong/Getty Images According to reports, President-elect Donald Trump has tapped recently retired Marine General James Mattis to be his secretary of defense.

The Mattis pick has been circulating as a rumor for weeks, and most of the commentary have focused on two aspects: 1) Mattis’ penchant for offering highly quotable, pithy, but slightly impolitic observations, and 2) to be confirmed, he would need Congress to pass a law lifting the restriction on recently retired general officers serving in this post.

The first aspect likely attracted Trump to Mattis. In their plainspoken defiance of political correctness, the two are birds of a feather.

The second clearly did not repel Trump from Mattis, and rightly so. Mattis is a very strong pick for Secretary of Defense and I believe a good case can be made to get Congress to lift the restriction.

There is little doubt that a Congress willing to confirm Mattis would be willing to pass the additional law required. As Robert Chesney, a professor of law at the University of Texas at Austin, explains, it is not quite as straightforward as renaming a post office. But lets not pretend it is a high legislative hurdle. Once a candidate has been cleared by the relevant oversight committee, most confirmations, even for very senior positions, are passed under unanimous consent procedures that fly through very quickly. Of course, a senator who wants to block a confirmation can put a hold on it or filibuster it. That sometimes happens, especially for controversial nominees, but if it does not, then a simple majority of the Senate can confirm an appointment. That same threshold is needed to pass the law that removes the legal restriction barring Mattis. While it is an extra step, it is likely not any more difficult than the confirmation process itself. In other words, if Mattis has confirmation troubles, they will occur at confirmation, regardless of the waiver issue. If he doesn’t have confirmation troubles, the waiver is manageable.

Also, it has been done before. In fact, within a few short years of passing the law forbidding uniformed military from serving as secretary of defense, Congress voted to lift it to allow General George Marshall to take the post. To be sure, in passing that law, Congress explicitly argued that it viewed this as a one-time exception that should not set a precedent; it wanted Marshall to be the first and last such exception. He was, for 65 years. Congress cannot legally bind future Congress in this way — this was a “sense of Congress” declaration anyway — but even morally, 65 years is long enough to view a second exception as exceptional.

In addition, while the logic behind the ban is a good one, it does not trump all other considerations. The logic for banning recently retired generals is as follows:

The secretary of defense and the president (commander-in-chief) collectively embody the National Command Authority and, as such, collectively represent the civilian in “civilian control.” They must actually be civilians to embody civilian control.

If they have prior military experience, they must nevertheless operate as civilians while being the National Command Authority. This is why President George Washington refused to wear a uniform or command troops in battle while president (commander-in-chief), even though his former experience as wartime commander arguably made him the most qualified battlefield commander in the republic. Ditto for President Dwight Eisenhower.

The secretary of defense is the person in government who embodies civilian control 24-7; he or she has no other duty, unlike the president or the Congress, the two civilian institutions named in the Constitution, and so on a day-to-day basis he or she IS the face of civilian control closest to the troops. That it is a civilian face, wearing civilian clothes, receiving salutes and courtesies from uniformed personnel, is a powerful visible symbol of civilian control.

Retired generals, especially retired four-star generals, never “retire” in quite the same way as do more junior military officers and enlisted. Even in retirement, their first name is “general” or “admiral.” They enjoy courtesies and influence that extend well into retirement, and so in some sense remain military professionals. That is why it is inappropriate for them to do things that are fine for other people to do, such as making partisan endorsements during campaigns.

Moreover, if recently retired as a four-star, that means the individual has reached the pinnacle of their individual service and so has developed exceptionally strong service loyalties and ties. It will be harder for such a person to then move into an honest broker position that is supposed to be above service rivalry. Such an individual may also have personal scores to settle, which again would complicate their new role as boss.

For all these reasons, as a general rule it is preferable for the secretary of defense to be more of a civilian than a recently retired four-star would be.

But exceptions can be made, and in this case, they should be made. Mattis has exceptional command of national security matters. He is not the only person in America with such a command, but he would be near the top of most people’s lists. Trump’s list is shorter than would customarily be the case because so many other logical candidates signed letters opposing him during the campaign, effectively taking themselves out of the running for consideration for a post like this. Moreover, Mattis is respected on both sides of the aisle. The secretaries that have been most successful in the past 25 years have been those who could command bipartisan respect — think Bill Perry and Bob Gates — and thus helped provide at least some small measure of insulation from partisan pressures. Finally, Mattis has shown himself to have the respect and confidence of Trump himself, one of the most exacting of requirements — a cabinet official that Trump does not respect and listen to is not going to be effective, regardless of qualifications. I think Mattis will also work well with Mike Flynn, who as national security advisor will have the challenging task of trying to coordinate policy development and execution across the Department of Defense and the other key agencies.

Speaking of Flynn, however, raises the civil-military question once again. Is it a bad thing to have so many retired generals in these senior positions? It is certainly possible to have too many retired generals — but I would not say two is too many. And if you were going to make the exception, Mattis is the one to make it for.

Moreover, the civil-military concerns, while important, can be mitigated:

Mattis will have to work harder than a more civilian nominee would to embody the civilian in civilian control. If you are going to make this exception, then you should make it for a general who has thought long and hard about civil-military relations. Not all general and flag officers have, but Mattis is among the small group who have done so. He co-edited a book on the subject (disclosure: I co-authored one of the chapters in that book) and I know his interest extends well beyond that. This long awareness and historical perspective will help him figure out a way to compensate for his generalness.

Mattis will have a leg up on most other possible secretaries of defense in winning the trust and confidence of the uniformed military. It is not widely appreciated outside the Pentagon, but these years have been difficult years for civil-military relations. The next administration, whoever took office, was going to face serious challenges. There is already a readiness crisis caused by the combination of the sequester and continued high operational deployments. The uniformed military has had to adjust in extraordinarily rapid fashion to changing social mores. The loss of the hard-won gains of the surge in Iraq, the uncertain progress in Afghanistan, and the ongoing threats of the Islamic states mean the military, which has borne the brunt of the global war on terror, is having to keep on fighting under emotionally and psychologically draining times. At the same time, intensified conventional and hybrid threats have contributed to making this the most dangerous security environment in 25 years. A steady and trusted hand at the helm will go a long way to smoothing the waters and heading off civil-military crises.

As for service loyalties, the chairman and vice-chairman posts show that it is possible to reach the top of one service and then earn the respect of the others. Mattis is fortunate in that he is joining the Department of Defense at a time when there is both a strong chairman and a strong rest of the Joint Chiefs. To be sure, sequester and other challenges have strained interservice comity, but it is to the great credit of current Chairman Joe Dunford and previous Chairman Martin Dempsey that the interservice problems are nothing like they were the last time this exception was granted in 1950.

And some civil-military concerns are just overdrawn. You do not “militarize” national security by having a retired military as NSA and retired military as Secretary of Defense. The canard that generals are like three-year olds with a hammer, thinking everything is a nail, is simply false, as Chris Gelpi and I have shown. Retired Generals may even be more cautious about the use of force; certainly Colin Powell was when he was Secretary of State. Of course, individuals can differ from a general pattern, but that is the point: case-specific judgments must be made and not some blanket assertion based on background.

All in all, this is an appointment I applaud, and I trust Congress will see it the same way. I am also hopeful this will give added confidence to good people who are considering joining the Administration. Many people I know would gladly follow Mattis into battle, literally and figuratively.

As a card-carrying member of the tiny group of specialists who fret about American civil-military relations on a daily basis, I feel pretty confident saying appointing Mattis to a post that requires a congressional waiver is one civil-military issue I will not lose any sleep over.