I found that book in the public library at about age 10. This was in the mid 60's and I grew up in Florida.
It was scary.
People today forget the 1950's and 1960's where nuclear confrontation was just another option.
US troops trained into the early 80's to deal with the effects of nuclear bursts on the battlefield.
Remember this
Interesting the novel’s flashpoint was Soviet-allied Syria, where we apparently have had troops now for years, getting hurt and killed. WTF.