Everyone has an oppinion on this, here is mine
- First I have to thank every single American taxpayer! While we in Europe have a much higher tax rate, there would be no space program if the Americans had not went up front.
- This directly leads to: NASA should continue to walk up front.
We have already manned launchers available (the Soyuz), we could adapt an Atlas V to carry a LEO-only CEV into orbit. To move on, we need a heavy-lift launcher. We need to be able putting 70 - 100 ton in LEO in one piece.
This is a capability we currently do not have, but which is required to construct any larger interplanetary craft from a limited number of launches. As Robert Heinlein said: Being in orbit is being halfway to anywhere.
I fully agree that one billion per year is not overwhelming, but it is a step in the right direction. Overcoming the economic crisis and the ongoing wars will drain enormous amounts of energy and money, so even a small commitment to support spaceflight is a good signal.