I take it, you agree with Rand that it's the national interest, not altruism, that is determinative for the just invasion. In the case of the third world, we might have a national security interest in some of these places; we, for example, would benefit from getting a say in how most Arab countries are run, as well as, of course, Afghanistan.
Would the Muslim nations benefit from American colonization? If we respect their culture (and we'd be foolish not to), they might; almost any civil structure out there would be an improvement over the sheiks, the Taliban, or the ayatollahs. (Which is the opposite side of Rand's "green light to invade an unfree nation" coin). The thing with objectivism is that it always meshes in nicely with conventional ethics. In the case on hand, an invasion of a Muslim land, which would oppress the legitimate Muslim aspirations, is not only unethical, but is not in our national interest.
But it looked like I was commenting on her position in intervention rather than her position on altruism.
I take it, you agree with Rand that it's the national interest, not altruism, that is determinative for the just invasion.
Not quite. It's determinative for the prudent invasion. If it were in our national interest to kill everyone in England, for example, it would still be unjust. It would also be unjust if it were our interest to kill everyone in Arabia.
I don't share Rand's view of altruism, since I'm a Christian, but I do agree with her that's it's a bad, and even immoral, basis for public policy. I don't hold the view on altruism many objectivists attribute to Christians, either. It's meritorious, but not obligatory. It is not meritorious, however, if the costs aren't born exclusively by the person or persons being altruistic, which is why the government shouldn't act altruistically.