He said 'until it's unaffordable' I guess he's using reserves like the way the US does on weapons and military, some of which isn't even for them.

He's investing in what he believes is a profitable investment. I'm guessing that he has financial advice from people that have studied this to a level that can understand it better than most people, and consider it a sound investment. With the intention at the other end being to use for the country. Everything accounted for, nothing going into senators back pockets, could be used to boost their health service and hospitals and whatever else. With countries less built up currently looking more favourable in the future, they're already in a good position.