It was universal at the time; Churchill also spent much of the war alternating amphetamines and barbituates. Plus the constant alcohol and tobacco, plus the underlying bipolar.
The only reason that the leaders of the 1940s didn’t destroy the entire world was that they didn’t quite yet have the technological ability to do so. Crazy times.
The cocaine effect you get from chewing coca leaves is rather different than what you get from snorting or injecting cocaine hydrochloride. It’s a slow, gradual release, filtered by the digestive system before reaching the brain; you can do it regularly for a lifetime without significant ill effect.
Only mildly relevant but… I recall reading personal accounts about the paratroopers who were dropped in 1st at Normandy. A disturbing number fell into deep sleep soon after landing. Often they chalked it up to the sudden relief of the enormous pent-up strain, both physical and emotional.
Years later, I happened to read a paratrooper’s account which mentioned that they’d been issued “anti-air-sickness” pills (for the 1st time) shortly before taking off. So it seemed more than coincidental, and likely that drowsiness was an unintended side effect of these pills. Misguided army leaders probably cost a number of lives and could have inadvertently undercut the whole mission.