Based on his record of accomplishment, Lt. Gen. H.R. McMaster promises to be a strong presence in the Trump administration in his role as national security adviser. He wrote the book, literally, on the problems that ensue when political considerations take priority over military strategy in waging war.

Selected for the post Monday, McMaster can be expected to bring the same approach in working to make sure politics do not take precedence over the interests of national security. This is particularly important in a Trump administration in which a pure political operative, chief strategist Stephen K. Bannon, was given a seat on the National Security Council by the president.

President Trump may have come to this decision belatedly, and only after his initial choice for the post resigned and his other preferred successors said no, but it turns out to be among the best appointments of his month-old presidency.

McMaster faces a tough task. According to numerous accounts, the career professionals who make up the bulk of the National Security Council staff are concerned about the troubled start under the new administration. Meanwhile, members of Trump’s inner circle are suspicious that holdovers from the prior administration are the sources of the news leaks plaguing the administration.

Getting this critical operation functioning as a team will be McMaster’s first challenge.

He replaces Michael T. Flynn, forced to resign by the president for withholding details from Vice President Mike Pence about Flynn’s call to the Russian ambassador during the presidential transition period. Trump lands on his feet on this one, because McMaster is a better choice than Flynn to be national security adviser.

McMaster, 54, played a key role in developing the counterinsurgency and troop-surge strategy employed by Gen. David H. Petraeus in shifting the Iraq War back in favor of the United States.

The new national security adviser showed his willingness to speak truth to power when he wrote his 1997 book, “Dereliction of Duty,” which faulted the Joint Chiefs for not taking a stronger stand when President Lyndon B. Johnson let political factors drive military decisions during the Vietnam War.

Now McMaster must prepare to speak truth to Trump.