How can we afford it? because scientific discovery turbocharges our economy. Why do we have such a huge biotech industry? Why was the internet mostly built in the US? Why are we the only country that has placed somebody on the moon, and have huge launch capacities?

Because we invested in those technologies and they paid off handsomely. What you are seeing is the result of "profit externalization"- laws like Bayh Dole allow universities to profit from the research they carry out under contract with the government.

Everything we did, we did because the alternatives were worse.