Let me see a show of hands. Who among you ever thought that a man with a nickname “Mad Dog” would emerge as a reasoned, thoughtful and nuanced secretary of defense?

Well, me neither.

Retired Marine Corps Gen. James “Mad Dog” Mattis has emerged as just that person. I want to sing the praises of the defense secretary, who over the weekend had the courage to speak reasonably — and in direct contradiction — to a reckless declaration that the president of the United States had made.

Mattis made a quick trip to Iraq and proclaimed that the United States will not seize Iraqi oil. Donald J. Trump famously said he intended to do that very thing if he were elected president. The idea, Trump said, was to deprive the Islamic State of the revenue it gleans from oil to fund its terrorist activities.

Gen. Mattis said, um, no … we aren’t going to do that.

Mattis is becoming arguably my favorite Cabinet official in the Trump administration. Heaven knows that there aren’t many of them for which I would express such admiration.

It is reasonable to wonder if Mattis is going to last for the duration of Trump’s term. Trump is known to be an impulsive, not terribly thoughtful individual. He says things that pop into his noggin without ever considering the consequences of what he says.

Seizing the Iraqi oil fields was one of those ill-considered statements. Ain’t no way we can do that cleanly and without shedding a lot of American blood.

Mattis, career military man that he is, understands a lot more about such matters than the commander in chief. I am delighted, too, that he is expressing himself with the confidence that those general’s stars have given him.

Thank you for your service, Gen. Mad Dog. Keep up the good work … if the president will allow it.