[everettForth]

This is all assuming that we don't have a space elevator.

tldr; it costs a lot of money to launch mass into space.

Sending 1 pound of water into space costs $50,000. This is more than the price of gold on earth. A space elevator changes the economics dramatically.

[nothrabannosir]

No, this is about the speed of the earth relative to the sun. E.g. even if we wanted to shoot, say, the ISS into the sun, it'd be hard. As soon as you point it towards the sun it will go into an elliptical orbit.

[gefh]

A space elevator takes care of a portion of the earth escape velocity, still leaving >20 km/s left once you get to the top.