If ARPANET failed then some other network would have evolved into the internet. Its not like networking technology was unknown outside of the military, heck most advances in networking and CS happen in universities, not via defense contracts.
Heck, the French had Minitel in the 80s while we had a loose network of BBS's and to be frank it wasn't the lack of network technologies that was the problem back then, it was the lack of a killer app. TBL delivered that in the form of the WWW. The WWW is network agnostic. There wasn't a day when people went "Whoa, T1s are now affordable for my LEC to sell to my ISP, I better get a shell account pronto!" It was "Whoa, there's email and colors and pictures and text and even video on my computer's modem via this thing called the web I'm seeing advertised on movie trailers and on product packaging?!?!"
... and who do you think funded those CS departments? It's all by grants, a lot of which is from the defense department, who has a lot of money to invest in high risk, high return, long-running projects with practical outcomes.
Saying 'some other network would have evolved' is a cop-out: clearly that would have happened, but it would have happened later and that could have cost us in terms of competitiveness. Same argument for GPS, except even more likely given the heavy investment in infrastructure needed to even get a basic implementation running.
Also the 80's are not the 60's, it's ridiculous to think that the networking technologies were not influenced heavily by the work funded by the military ... hell the only reason killer apps could be created was because the technology was so pervasive that it made sense to write them.
And GPS, self-driving cars, and ARPANET are only what I came up with offhand because I was too lazy to check. Add ENIAC and radar to that list, both of which were developed specifically for military purposes but (obviously) later had wide-ranging practical civilian applications.
Yeah but whats the context? How much of that directly to programs like we're talking about vs money via tuition, fees, etc.
I think this is really impossible to quantify, but from a rational POV we can look at countries with small defense spending and see that they have healthy univerisities and healthy economies as well as healthy technological advances (again my example of the early french 'internet'). Tim Berners Lee was not only NOT an American but not funded by the DoD. His www application is what got the ball rolling. The network or protocol didn't matter, we can run http over anything. Same with Linus Torvalds, another non-American non-DOD funded star. We were sitting on nice networking tehcnology and wondering when Joe Public would see the wisdom of anything other than AOL and dialup (two very American things). It took a an Englishman at CERN and a Finnish student to give us WWW on Linux. Whats the Finnish defense budget look like?
A big bloaty DoD and the war on brown people is not a requirement for technological progress. If anything, it holds us back.
Heck, the French had Minitel in the 80s while we had a loose network of BBS's and to be frank it wasn't the lack of network technologies that was the problem back then, it was the lack of a killer app. TBL delivered that in the form of the WWW. The WWW is network agnostic. There wasn't a day when people went "Whoa, T1s are now affordable for my LEC to sell to my ISP, I better get a shell account pronto!" It was "Whoa, there's email and colors and pictures and text and even video on my computer's modem via this thing called the web I'm seeing advertised on movie trailers and on product packaging?!?!"