Brunei has oil. Australia has gold, coal, rare earths and iron ore. If they run out, they have nothing.

Malaysia refines Australian rare earth minerals. Not because the technology is secret or anything, but because we would need to pay far too much to our politicians to get permission to do it here.

Singapore... okay good point there.

Malaysian politicians might not be as good as Singapore's, but they are still not as stupid as some. At least in economic matters.