What’s worse: Launching a disastrous military campaign under false pretenses to achieve goals you wrongly believe are attainable? Or launching a disastrous military campaign you know is doomed in order to help your party win an election?

I ask in light of today’s New York Times story about how President Obama asked the CIA a while back whether arming rebel forces – pretty much the agency’s signature strategy — had ever worked in the past.

He was told that it almost never has.

But then in June, once the political pressure for intervention in Syria got too great, he did just that — sending weapons to rebels fighting the Syrian military.

Yes: He knew better, but he did it anyway.

Political (and media) pressure was also a major factor behind last month’s shifting of those gun-running efforts to counter the Islamic State, instead of the Syrian military – and the launch of ineffective if not counter-productive strikes by U.S. planes and missiles.

Obama could have leveled with the American public and said: Look, there’s not much we can do to help over there. Pretty much everything my best people have come up with only makes things worse. If there’s a solution at all, it’s for the Saudis and the Iranians and the Turks to make this their problem.

But that probably would have been cast by the elite media — not to mention Fox News — as surrender, costing the Democrats another few House and Senate races.

So it wasn’t even a possibility.

As it happens, Syria is hardly the first or most significant place Obama has used his power as Commander-in-Chief in ways that get people slaughtered, even though he knew better, primarily for political purposes.

Obama’s biggest such decision killed a lot of American servicemembers who he sent to fight and die in Afghanistan.

During his 2008 presidential campaign, which was marked by his opposition to the war in Iraq, then-Senator Obama’s vow to re-engage in Afghanistan was seen by many as a ploy to avoid being cast as a dove, first by Hillary Clinton and then by John McCain.

What’s not clear to this day is precisely when Obama knew better; when he realized that the war in Afghanistan was hopeless.

By inauguration time, that conclusion seemed fairly obvious to many foreign-policy watchers. So why not him?

But one month into his presidency, Obama announced he was sending more troops there – 30,000, as it would turn out. Despite the obvious lack of what he himself had frequently described as a must — an exit strategy — he increased the number of troops in Afghanistan by 50 percent. And the monthly death tolls shot up.

Over 1,600 American servicemembers have died in Afghanistan since the summer of 2009 — well over half of all the dead during the entire war – along with countless Afghans.

There were public signs in November 2009 that Obama was “rethinking” his plan. David Sanger, in his book Confront and Conceal, wrote that Obama actually began a “reassessment of whether the war was as necessary as he first believed” even earlier, in the summer of 2009. (At an off-the-record June 2009 dinner with historians the “main point” his guests tried to make was “that pursuit of war in Afghanistan would be for him what Vietnam was to Lyndon Johnson,” Garry Wills wrote later.)

And according to Sanger’s murky sources, the recognition that things were hopeless came at the latest by June 2011.

But it wasn’t for three more long years — until this May — that Obama finally announced U.S. troops would be out of Afghanistan by the end of 2016.

Which brings us to the question I raised at the top.

George W. Bush’s decision to go to war in Iraq sent vastly more people to their deaths than anything Obama did – nearly 5,000 U.S. servicemembers, plus over 100,000 Iraqi civilians – and left as many as half a million U.S. servicemembers wounded or otherwise permanently damaged.

(Obama’s latest doomed-to-fail show of force explicitly keeps U.S. servicemembers out of harm’s way. )

But Bush at least thought the war in Iraq would do some good.

He was incredibly wrong, mind you. He was both delusional — and actively manipulated by neocons like Dick Cheney (who believe the application of American power is always and inherently a good thing). He intentionally misled the public about his real reasons for going to war (the terrorist attacks of 9/11 were an excuse, not a reason; there were no Iraqi weapons of mass destruction). His eventual goal was both unachievable (a sudden flowering of pro-Western democracy in the Middle East) and perverse (American control of Iraqi oil fields). His methods (firing all the Baathists; trying to install a corrupt puppet) were spectacularly misguided. Much of the rest of his presidency was consumed with sectarian warfare in Iraq and new lies to cover up the old ones at home. And the end result was a massive human rights catastrophe, including torture of U.S. detainees, a refugee crisis, mass casualties, social disorder and – finally – the Islamic State.

Bush also certainly saw – and exploited — the political upside of being a war president.

But he didn’t let loose the dogs of war simply because his political operatives told him it would poll well.

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