What makes you think that's a lot of money? 500 Million is the cost of a couple of hundred cruise missiles. The Iraq war costs the USA $200 million per DAY. Governments do nothing out of charity, there is always a reason for their actions. The reasons for aid donations are simple. Donation money is a small drop in the ocean and if it leads to prosperity and stability (big if, I know) then it pays off for everybody, a stable and peaceful world is a world where countries can trade and people can work towards prosperity rather than a world where they spend their lives dodging terrorists and grubbing in the dirt. It also has the effect of boosting the donor countries political and economic power in the regions they donate to. Look at China's massive donations to African countries, their donations dwarf western donations and in 20 years time they'll be the ones who control Africa's resources - thanks to the money, infrastructure, and training they've donated.