From Niall Ferguson, author of The Ascent of Money:
There's an interesting concept that underlies this passage from Ferguson. It's something I think we all can relate to.“It's all very well for us to sit here in the West with our high incomes and cushy lives, and say it's immoral to violate the sovereignty of another state. But if the effect of that is to bring people in that country economic and political freedom, to raise their standard of living, to increase their life expectancy, then don't rule it out.”
It's the notion that, when your back is against the wall, you will do whatever it takes to make sure those that you care about get what they need.
Example: I constantly hear blame tossed around about "poor people" in America's big cities struggling with illiteracy, drug abuse, and violence. "It starts at home," they usually say in a condescending manner. As if all it'll take is for parents to teach their kids better. But what if those parents are working two jobs to barely cover the mortgage, and are never at home, and that's something that happens all across the neighborhood? And if access to jobs, good schools, and good grocery stores is nonexistent? Does peddling drugs seem that much of a stretch?
A related notion is that, while you're going through something, you don't know what it's like to not be going through it. Then when you have the wisdom of being on the other side, you strangely forget what it was like to go through it.
Example: during college, I fully drank the Kool-Aid of student organizations and got very deeply and emotionally involved with them. After a year of working in the "real world," I watched my slightly younger friends (still in school) obsessing over these same organizations, and I found it odd. "They just don't have perspective yet," I thought, as I found a new Kool-Aid to drink (my job). I had forgotten what it felt like to go through that process and how instrumental it was to me becoming who I am now.
All of this is just another re-articulation of Maslow's Hierarchy of Needs. Before we can start discussing higher, more idealistic notions of the world, we first need food and safety. Then we seek out belonging and purpose. Then we keep moving up and around the hierarchy, based on our circumstances and development. But then and only then.
If those bottom "animal" needs aren't secured, I think we're willing to do whatever it takes to make sure they are. That's not a fault of individuals, but rather of the system itself.
Of course, this doesn't justify anything, but it does serve as an adequate explanation.