Did the government drug test to join the military during Vietnam?

I don’t remember it as quite that bad, but the social stygma was certainly much more prevalent than today.
The attitude toward drugs was much different then too. Meth wasn’t an issue, but amphetamines were fairly prevalent. They were commercially produced and many women were given scrips for weight loss. I remember moonlighting and using them occasionally to cope w/ the loss of sleep. They were used by the military, but on a very limited basis. I’ve done some searching, and some recollection, and I’m sure that there were no commonly used tests for drug use, especially pot. I’m fairly certain that urine testing wasn’t viable until very the late 70’s, or early 80’s and routine testing didn’t begin for a couple of years after that.
The antiwar fervor didn’t start gaining popularity until '68 and even then many people still supported the war.

The Privacy Act became law in 1974, before that privacy was a hodgepodge of laws, many contradictory, or even ignored.

I remember the big purges in the Navy in the 70s and early 80s. Not only were they kicking out the druggies by the hundreds, they adopted a program called “Operation Upgrade” (which we all called “operation flush”), wherein they were dumping the most undesirable elements out of the service and back into society. I was asked by my company commander to give him a list of men I would like to see gone, and many of them did indeed disappear.