War is a great way for the corporate media and the government to work together to manufacture public opinion. The Syrian airstrikes earlier in the month was a moment of circling the wagons for the movers and shakers, as the media was able to demonstrate their abilities to Trump and co. that if they work together then poll ratings and viewership numbers go up. It's win-win for the establishment.
speculating because I have not spoken to a publicity offer at the Pentagon.
They view popular suppport of military actions as an important strategic objective because they require congressional support for their procurement budgets, and executive support (capitulation to?) for their planned operations. War is political and they do this kind of thing to manage the politics of war.
The immediate followup question then becomes: why does the Pentagon view bragging about weapons as effective for gathering political support for their wars?
I can't say that I have a clear notion of why they believe this. Perhaps because it plays to the pornographic nature of the mainstream media in the U.S., which enthusiastically embraces spectacles of violence. Perhaps because they are correct to believe that a majority of Americans are stimulated by war porn. The media certainly believes that. They get the ratings. Or perhaps you're right and its less sophisticated than I am imagining. Maybe the Pentagon really does think it's a kind of accomplishment worth bragging about.
Because the USA government funded ISIS to begin with? There is no advantage to removing ISIS they aren't a threat to the US but are anti-Assad so they support our interests in the region indirectly.
Furthermore they are great scapegoat for an executive government power grab and building a surveillance state.
It doesn't hurt that prolonged military engagements do wonders for the profits of the military-industrial complex either.
I'm ALL for taking out ISIS. But, with carpet bombing huge areas, the likelihood of unintended collateral damage is very high. Which brings us to the general attitude of the U.S. in war - "When it comes to innocent lives, only U.S. lives matter!!"
There's ZERO chance that the U.S. would tolerate collateral damage on it's own citizens in the name of getting ISIS, so why accept the possibility of non-American causalities?