Stargate is the way the US is competing with China, and it will soon be involved in weapons systems. It will be important for all first world nations to keep. Hopefully the EU will wake up and smell the coffee if you will. Falling behind in this race will make it very difficult to ever catch up.
500 billion is a lot of money, and there will needs be a huge amount of energy to run it all. That's the next giant hurdle to overcome!