With any war movie, the safe audience bet typically favors the immediate, graphic horrors of battle. That way, when you see a title such as “Hacksaw Ridge,” you know a director (in that case Mel Gibson) will be operating with a cinematic license to slaughter. Espionage makes for subtler, trickier storytelling. “Operation Mincemeat,” now purring along, confidently, on Netflix, takes as its subject a singular feat of deception cooked up by British intelligence in 1943. How decisively the operation turned the Allied tide against Nazi Germany is up for historical debate. But the men and women of M…
