Steve Rogers: I know guys with none of that worth ten of you. I've seen the footage. The only thing you really fight for is yourself. You're not the guy to make the sacrifice play, to lay down on a wire and let the other guy crawl over you.
Tony Stark: I think I would just cut the wire.
Steve Rogers: Always a way out... You know, you may not be a threat, but you better stop pretending to be a hero.
War is the most wasteful of human activities. It's designed to do one thing - destroy. That destruction comes in the form of lives lost, property damaged and societies fractured. It's all so very wasteful.
It also requires an utter level of conviction; you must completely overcome your enemy, reduce them to a quivering mass afraid to ever lift a finger in your presence again or you must "...plant your foot on his neck, and keep him that way forever, lest he spring up and slit your white throat."
There is, in my mind, only one valid justification for war - and that's to stop the fatal suffering of other human beings at the hands of oppressors. Up to that point you have many, many tools for coercion; legislative, advocacy, civil disobedience, million person marches, more nuanced tactics of persuasion. When the guns start picking off the people, that is when you must recognize all other efforts have, in exclusion, failed - and that's when you supplement them with extreme prejudice.
The conflict in Syria is one of those times. It is incumbent on world leaders (yes, many of whom have blood of some kind or other on their own hands) to do something to protect the innocent. That's the whole point of being a leader.
Now here's where I stand apart from many. I am not in favour of armchair military tactics that keep the aggressor out of harm's way. There is, in fact, a rule for that - do unto others as you'd have them do unto you. If you are prepared to put a bullet into another human being because you believe it is necessary, you must be prepared to take one back.
To declare war on someone and expect them not to retaliate if folly. To try and take the risk out of war for yourself is equally short-sighted - it tends to involve harsh measures like landmines, chemical weapons and drones, escalating the inhumanity of combat. When you keep your skin out of the game, you keep your enemy at a distance, making it easier to dehumanize them. The person you can't see can be an animal, a beast, a sub-human creature that needs to be put down at all costs - meaning, the ends justify the means. That's the approach Assad has taken, as have so many dictators before him.
When you look 'em in the eye, they are simple another soldier following orders on behalf of a cause that's been sold to them in the most flattering terms possible. They have families just as you do; they are as frustrated, tired and questioning as you are. If you have to kill them - and you may have to - recognize that killing for what it is and remember.
This is the same reason I believe he who passes judgement should wield the sword. Leaders calling for war from the comforts of plush offices are playing testosterone-fuelled games using the lives of others as their pawns. Assad feels like the Big Man on the Syrian campus; he'd feel a little bit differently if the carnage being done on his orders landed directly on his doorstep.
There are all kinds of reasons why modern leaders don't lead from the front - bigger theatres of war require broader line-of-sight to manage multiple engagements in an effective, coordinated way. When the people calling those shots, however, have never experienced war in person, then there's a good chance that all they see are hills on maps. The Bloody Great War I is full of such stories of lives destroyed because leaders didn't bother to get the lay of the land.
Politics is this kind of warfare writ large - leaders try to remove themselves from the consequences of their direction, fostering a chain of unaccountability. You can always spin your way out of any crisis you have brought on yourself. Everyone that gets hurt along the way is simply collateral damage. By enabling leaders because we think that will serve our own best interests, we fuel the problem. The role of a leader's team isn't to protect their leader but to empower them and provide them with the best counsel possible, whether it's palatable or not. Leaders should wear the weight of their decisions personally - it's not a privilege, being in charge, but a responsibility.
War is sacrifice; in situations like Syria a necessary one, but a sacrifice none-the-less. If you're going to commit to combat - if you're going to commit your own forces to combat - have the guts to internalize what you are doing and do it properly. That means boots on the ground, preparations at home and a never-ending commitment to try and make non-violent alternatives work. Destruction of the enemy is never the goal - you can't do that without becoming a war criminal yourself. Keeping your foot on the throat of your enemy isn't sustainable, either - revolutions are born that way.
If a leader is to commit to war, they should do so not in a bid for self-preservation; in fact, they should do so from a mindset of never asking their troops to do that which they would not. That means being ready to put your own life on the line as well. That kind of conviction discourages sloppy and wasteful planning, but it is also powerful beyond recognition - there is nothing more terrifying on the field of combat than an entire force that, from the top down, is prepared to put the mission before all else, including themselves.
At the end of the day it's not a matter of us vs. them; it's one world, and we all live in it together, or we can die alone. There is nothing heroic about killing someone else; the true heroes are those ready to die themselves so that others may live.