Let's cut those in half and talk again about SETI, which I would be happy to fund a hundred times over if it meant less killing, fewer unjust incarcerations for victimless crimes, more economic equality, and less concentration of money and power in the hands of the elites.
Eg imagine if Iran just decided to stop oil shipments through the Strait of Hormuz with their military. How would you deal with this without a sizable military yourself?
Edit: or imagine that some country decides that they don't like goods related to the US going through Panama so they decide to occupy it. It's not US territory, but the loss of that will harm the US economy.
Seriously, the USA aren't the only armed forces that patrol the area.
The UK has a significantly smaller defence budget than the USA does. Which kinda proves my point.
Elsewhere the UK assists the US in Syria and Afghanistan. It's not the other way around.
But feel free to tell me how great the american way of doing things is. What with fantastic provision of basic healthcare for its citizens, and sensible gun control oh yes and affordable education.
Look at Crimea if you want an example of what can happen if there's no force that can back you up.
In my opinion, these money are better spent on any other applied or fundamental research.