TCP is NOT the protocol of the internet...
TCP-IP is !!
TCP was one of the founding blocks, and an important one at that, but not the only one. It ought to stand as such as one of Vint Cerf contributions.
Another error that ought to be corrected: the packet transfer technology that went in the IP (internet protocol) (the IP half of TCP-IP) was actually developped a few years earlier (1974-75) by Louis Pouzin.
Leonardo da Vinci sketched the helicopter yet no one seriously will credit him of inventing the helicopter. He did contributed to such an idea and that's one of the reason we consider him a genius.
Same with the internet. A very small number of people contributed the early founding blocks of the internet. None contributed them all.
As for the date the internet went live the routers switched to the new TCP-IP protocol at a very precise moment, and it had to be done worldwide for obvious reasons.
That moment happens to have been 0h00 on January 1st, 1983.