NASA and MITRE were the first to invent and deploy cable modems. Martin Cooper invented cellular technology, so that can't be attributed to government. The microprocessor was developed independently by three different groups, one government, two not. GPS is a government invention. Internet is a (largely) government invention.
The private and public sectors have been so intertwined for so long that it is hard to really say "Oh, the government did this" or "Oh, no, private sector is responsible." The only way to actually have a successful high-tech industry is to have both parties involved. Mixed economies are obviously the superior economy.