Comment by fragmede

The latest (series 9) Apple Watch has (up to) 2 GB of RAM and can do billions of instructions per second.

In 1966, the mainframe to use was the CDC 6600, able to do ~3 million instructions per second (MIPS), with kilobytes, possibly a megabyte of RAM. The US government had a good number of mainframes, of a wide variety, but they wouldn't be able to reach the Apple Watch's computing power.