President Trump promised to destroy ISIS, and the movement of conventional American ground troops into Syria marks a substantial departure from the Obama administration’s feckless policy. Trump is delegating authority and allowing his new Defense Secretary and responsible generals make operational decisions, rather than running the war from the White House. The Pentagon has already increased the pace and focus of American efforts in Syria, which hopefully is geared to the objectives Trump and the American people want: Annihilate ISIS and get out.

Among Napoleon’s famous maxims was one admonishing the indecisive. “If you set out to take Vienna, take Vienna.” The U.S. Army embodies this maxim in its Field Manual (FM 3-0) with the first of nine basic principles of war: “Direct every military operation toward a clearly defined, decisive and obtainable objective. “

Maxims and principles are fine, but these things are much easier said than done. Any military maneuver involves substantial risk and uncertainty, but the Syrian quagmire complicates operations there. Four national militaries now operate in northern Syria (American, Russian, Turkish, and Syrian) as well as a confusing welter of Syrian rebel groups, Kurdish militias, Syrian auxiliaries (e.g., Hizb’allah) as well as ISIS itself and any allied organizations.

A complete military dilettante, Obama nonetheless dictated strategy and even minor operational decisions against ISIS to the point of counting bombs dropped and the number of Apache attack helicopters permitted in theatre. While the left is fond of making ridiculous comparisons of Trump to Hitler, it was the German dictator and former Bavarian infantry corporal who insisted on shuffling around Nazi battalions rather than letting his more competent generals to conduct operations.

Trump’s ability to effectively delegate authority, something Obama clearly lacked, is indicative of his superior management experience. Trump’s selection of James Mattis as Defense Secretary was bold and inspired. Mattis is uniquely equipped by experience, knowledge, and temperament to ride herd over the generals who will have to translate Trump’s goal of destroying ISIS into reality on the ground.

That may not be as easy as dropping more bombs. Conversely, Trump and Mattis must also ensure that the generals conducting operations (who are still largely Obama’s guys or at least appointed by him) do not fall victim to excessive caution, incrementalism, or fantasy, which have largely characterized the campaign against ISIS so far.

As noted here, the allied bombing campaign against ISIS has been characterized by a remarkable lack of bombs dropped per sortie, which supposedly has caused enormous casualties for ISIS. Were these statistics credible, which they are not, ISIS’s continued resistance would be one of history’s greatest military feats. Presumably, we can attribute this absurd situation to the Obama White House, but the sorties and stats were mostly generated by the same generals that now will be conducting the campaign in Syria.

Mattis not only has to deal with the Pentagon’s Obama hangover, but also some ideas which have infected the military even before Obama, and which still are a drag on American (and in general Western) military performance.

Some are leftovers from the days of Colin Powell, who introduced two questionable concepts to American military doctrine. One is the concept of overwhelming force, sometimes called the “Powell Doctrine” which is really a list of preconditions that if applied hinder and complicate military action to an extraordinary degree, and require in the event of action, establishing conditions in which a victory is a guarantee. This idea worked one time, during the Gulf War over which Powell presided, but the conditions of that campaign were unique and heavily advantageous to the coalition that waged it.

Those conditions have not recurred and likely never will again. Mattis knows this as well as anybody, having subsequently commanded one of two major American task forces that waged a much less opulent campaign against Saddam Hussein a decade later.

Powell’s reaction to the Iraq invasion was a bon mot he got from Pottery Barn -- If you break it you own it -- a military non sequitur if there ever was one. Traditionally, the function of armies is precisely to break the other guys stuff, and make him pay for it. Powell got it exactly wrong, but unfortunately it is an idea now accepted by many in and out of the armed forces.

Another bad trend is the hypersensitivity and misapplication to modern law of war doctrines. The American military currently follows law of war statutes this country is not a party to, most particularly the 1979 Protocol Additional to the Geneva Conventions, which forms the bases for onerous rules of engagement that hamstring military operations. At times it seems like we and the Israelis are in a race to see whose lawyers can hogtie their own armed forces more completely.

For now, the American operation in Syria seems to be following the course of the operation against ISIS in Iraq. This means limited bombing and ground operations in support of various anti-ISIS groups, and directed at a particular urban target, Mosul in Iraq and Ramadi in Syria. If Mosul is a gauge, the prospects for a quick resolution in Ramadi are not good.

Still, there is no evident popular groundswell of urgency in the country to do more, and Trump ought to be reluctant to mount a substantially more robust effort unless he can garner that support. Even if that becomes desirable, such a deployment may not be practicable given the many competing and/or “friendly” armies in the area.

For now, Trump is right to give Mattis and his generals the reins, adding support as they call for it. The military generally appears happy to have Trump in the White House, though there are some dissenting voices.  But unless things take an unexpected positive turn in our favor relatively soon Trump has a difficult decision. If he is to honor his election pledge regarding ISIS he will have to do more, and make sure the military completes its objective.