Undoubtedly, there are more problems abroad than there are at home--pick out any macro or micro economic indicator you want to support this. I know I have always felt compelled to help those abroad because of the images of destitution I see in the news and the fact that my quality of life is significantly better than most people in the world for absolutely no reason other than luck. I know that, using purely cost-effective based metrics, my resources are better spent abroad because they can go further there. What might be able to fund a small portion of a doctor's salary at a health clinic in the US could actually provide life-saving medication for several people in the developing world.
However, I also know that I am not African (or Asian or South American), I will always be an outsider and I have limited experience with foreign aid. I sometimes question if foreign aid can actually decrease (or eliminate) poverty and know that many aid projects are inefficient at distributing resources precisely because they are an external force on the community or the country. (See also White Man's Burden and Dead Aid.) I can gain experience in international development, but I will never actually have the same life experience of those I am trying to help, nor be from the same culture of the communities I am working in.
On the other hand, I am from the United States and I have a large understanding of the history of the country, it's culture and it's issues. I know that I will never have the same life experience as those I am trying to help here in the US as well--as I come from a privileged background--but I have a greater understanding of things than I would in a foreign country. There are many issues here to work on and I have trouble saying that they are not as worthy of my support simply because they require, comparatively, more resources.
Which brings me back to the Fourth of July. Maybe it was just the patriotism in the air, but as I chewed over my bacon veggieburger, I felt like my place is here and the people I want to help are those around me. It reminded me of the chorus to the Little Steven song "I am a Patriot:"
I do not want to discount the efforts abroad, because I believe those are important too. They both require equal support. For me, I've decided to try to navigate this support by committing my time--which Warren Buffett called the most precious asset--to domestic issues, while committing my money to organizations working abroad.
I am a patriot and I love my country
Because my country is all I know
I want to be with my family
With people who understand me
I got nowhere else to go
Of course, I could draw a different conclusion from this discussion and say that the differences between the developing world and the developed are not as distinct as one would think, therefore their problems are comparable and we shouldn't create false dichotomies. But the spectacular DC fireworks display instilled quite a bit of love-of-country in me, so I will leave you with this bleated happy Fourth of July message (sorry for the language):