Most countries don’t invest much in space. As a percentage of GDP, US is second only to Russia in government civilian space funding. (Given US GDP is over 12 times that of Russia, US spending is higher than Russia in absolute terms.) For your dream to come true, other countries have to increase their expenditure. (My own country Australia is among the guiltiest here - the Australian Space Agency’s budget is less than 10 million a year - it should be a hundred times that.)

Widely-shared responsibility and widely-shared credit don't have a great track record for accomplishing amazing and bold things.

Competing nationalism can do wonders for technology (that's how the space race got started, and look at all the inventions we benefit from now that came from NASA).

On the other hand, competing nationalism leads to war...