We launched a live sub missile but the warhead and range was much less.
In 1962, we conducted a rather famous live missile test, Starfish Prime. It was a 1.4mt W49 warhead carried to an altitude of 250 miles over the Pacific by a Thor missile.
 As seen from Honolulu 841 miles from ground zero |
What was interesting about the blast was its unexpectedly large electromagnetic pulse. According to the Wikipedia,
The EMP observed at the Apia Observatory at Samoa was four times more powerful than any created by solar storms, while in July 1962 the Starfish Prime test damaged electronics in Honolulu and New Zealand (approximately 1,300 kilometers away), fused 300 street lights on Oahu (Hawaii), set off about 100 burglar alarms, and caused the failure of a microwave repeating station on Kauai, which cut off the sturdy telephone system from the other Hawaiian islands.
Radiation belts it left behind in space also knocked out several early communications satellites.
Back in those days, electronic gear was mostly vacuum tubes and discrete semiconductors. These are more resistant to EMP than today's microelectronics.