What were the motives stated for for the US attacking Syria or incentives to do that?
It doesn't seem like there was any immediate threat from Syria to the US. (After all, they neither have ICBM's nor a blue water navy to be able to attack the US.) The targets of the Syrian attack were not US citizens. Is the only reason to proactively protect rebels from future attacks?
Part of the reason is purely domestic political (which, of course, a lot of foreign policy reasons boil down to, in many countries).
In case of Trump and Assad, there were actually several independent domestic factors:
President Trump's base is the same people who criticized President Obama over setting 'red line' for Assad over use of chemical weapons and not doing anything when he did use them (because they happen to think that gassing people with poison is Not a Good Thing, even if the gassed people are Muslims in Syria).
As such, Trump - contrary to his own non-interventionist stance - was forced to act decisively lest he lose the support of his base as "just a next Obama who lets Assad gas his people with impunity".
OTOH, if he acted weak on Assad, he would give basis to the Democrats and left wing to attack him as "Russia's lapdog", since that would play right into left wing narrative of him being Russia's Manchurian candidate.
As such, he was forced to act decisively to maintain appearance that he isn't just dancing to Putin's tune.
Yes, the deep irony of Obama and Trump role reversal on both these points isn't lost on me :)
There could be an argument made that Trump is also angling for general approval bump in a "rally around the flag" manner.
We don't have good polling to see if that worked, yet, but FiveThirtyEight prediction is that it may not have a huge or permanent effect.
The polling so far clearly support conclusion #1 and probably #3, but isn't clear on whether #2 worked in Trump's favor at all (supporting 538's #3)
A HuffPost/YouGov survey finds 51 percent of Americans support the president's decision to order the airstrikes in retaliation for a chemical attack last week that killed civilians in northern Syrian.
Thirty-two percent of Americans are opposed to the strikes and 17 percent are uncertain.
Among Trump voters, 83 percent support the president's decision, while just 11 percent oppose it.
Because people are squeamish about chemical weapons. Remember, President Obama (not a hawkish president by any stretch) said this
We have been very clear to the Assad regime, but also to other players on the ground, that a red line for us is we start seeing a whole bunch of chemical weapons moving around or being utilized. That would change my calculus. That would change my equation
Now, it turns out it was an empty threat, but it's noteworthy that he felt that he needed to do this over chemical weapons. As has been noted, this doesn't affect the ability of Assad to kill people with other means
Look, I get why — morally, strategically, and legally — chemical weapons are different than conventional ones. But if my entire family and village were wiped out with bullets and bombs rather than chemical weapons, I wouldn’t draw much solace from any of these distinctions.
As to what we got out of it? Public Relations
The difference, as Trump admirably admitted from the Rose Garden, is that he’s president now and that changes your perspective on things. It’s always easy to throw brick-bats when you have no responsibility. Now he’s looking at the prospect of being the president who, in effect, sanctioned the use of chemical weapons, a violation of international law. As he put it in his statement Thursday night:
It is in this vital national-security interest of the United States to prevent and deter the spread and use of deadly chemical weapons.
There can be no dispute that Syria used banned chemical weapons, violated its obligations under the Chemical Weapons Convention, and ignored the urging of the U.N. Security Council.
That is a sound argument. But it was just as sound in 2013 [when Trump decried action in Syria]. Trump’s real motivation seems to be the fact that babies were “choked out” and that he saw it on TV. And it is this apparent fact that should give everyone — supporters and critics alike — the most cause for concern.
Ultimately this was an easy win. Trump got
The motives are primarily financial and geopolitical. U.S president Eisenhower warned about in his farewell speech, saying:
In the councils of government, we must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military-industrial complex. The potential for the disastrous rise of misplaced power exists and will persist. We must never let the weight of this combination endanger our liberties or democratic processes.
And by doing so, coining the term, the military-industrial complex.
Today however, that arms industry, is quite larger than it was back then. That military industrial complex still has a lot of economic interest in any war where the American tax payers are left to foot the bill.
Geo-politically, regime change in Syria would deny Russia the only Mediterranean naval base they currently have. It would also be a major blow to Hezbollah and Iran.
The other answers here are intriguingly absent of reference to military contractors. They spend lots of money lobbying politicians to ratchet up the military because a lot of money goes to the contractors during times of conflict and war. By chemical weapons apparently being used in Syria the US Government has been given an easier justification for escalating the conflict.
There is a lot of money to be made off taxpayer money during times of war and this system has consistently pushed the US Government toward war.
Edit: Since you guys asked... @machavity I'll be honest, I thought we were at the point where lobbying was an openly accepted occurrence but if you insist on references I can pull up some basic ones, although there is a plethora more out there. Military contracting companies spend over $100 Million per year on lobbying politicians. Since government spending into the sector increases during war-time, profits in the industry typically do as well.
The irony is that some of the other answers on here (not as downvoted) rely on the face-value statements of politicians and government divisions which have terrible track records and whose credibility, in my opinion, is dubious at best.
Ultimately, if the basics of my assertions here are contested I will simply point users to the (relatively) recent Duke Cunningham scandal which gave a rare glimpse into how the "meat is made" in Congress with regards to military contracts: [link] (https://en.wikipedia.org/wiki/Cunningham_scandal)
[link] (https://www.opensecrets.org/lobby/indus.php?id=D)
[link] (https://www.usatoday.com/story/money/business/2013/03/10/10-companies-profiting-most-from-war/1970997/)
Otherwise this is just your opinion? Let me quickly write a blog post to update the sources...
Commented
Apr 11, 2017 at 11:55
I'd suggest the war in Syria is at least partly fueled by the Qatar-Turkey pipeline:
"The discovery in 2009 of a new gas field near Israel, Lebanon, Cyprus, and Syria opened new possibilities to bypass the Saudi Barrier and to secure a new source of income. Pipelines are in place already in Turkey to receive the gas. Only Al-Assad is in the way. Qatar along with the Turks would like to remove Al-Assad and install the Syrian chapter of the Muslim Brotherhood. It is the best organized political movement in the chaotic society and can block Saudi Arabia's efforts to install a more fanatical Wahhabi based regime. Once the Brotherhood is in power, the Emir's broad connections with Brotherhood groups throughout the region should make it easy for him to find a friendly ear and an open hand in Damascus."
