TIL: Today I Learned...
I'm sure you meant the Allies and not NATO, but yes, that was an amazing and well lived life.
The OSS was the WWII precursor to the CIA when it was founded in 1942 by President Roosevelt and headed by John Foster Dulles. The UK's equivalent was the SOE, or Special Operations Executive, now those guys were known for bombings, targeted assassinations of Nazi officials, high-ranking German generals, luminaries like assassinating Reinhard Heydrich in Prague in 1942 in an open-air Mercedes-Benz, SOE agents also collaborated with underground Norwegian saboteurs in mid-1943 on bombing the German heavy-water distribution plant in Telemark, Norway (heavy water is one of the main components of creating a nuclear weapon), SOE operatives and Norwegian saboteurs later on destroyed large stockpiles of enriched uranium the Germans had stored on a commercial ferry, thinking Allied agents wouldn't kill innocent people to prevent them from moving nuclear materials. They were wrong because the commercial ferry was blown up along with the enriched uranium on a Norwegian fjord.
Those missions, essentially, permanently crippled Germany's war-time effort to complete and build a atomic weapon, although historians believe they did experiment on using two low-key, low-grade "dirty bombs" in western Poland in January 1945. "Dirty Bombs" are essentially sheetty nuclear weapons because they spread nuclear material instead of concentrating it within a certain, specific proximity.
After WWII ended, IIRC in late May 1945, Allied investigators found tons of buried enriched uranium in Bavaria and it was calculated that German military scientists via Ahnenerbe and RSD, SS had created maybe 4-5 tons more of enriched uranium, a working Nazi prototype atomic bomb conceivably couldve been made operational by end of WWII and if Hitler had earmarked more funding for nuclear weapons research (which he didnt understand and frankly, IMHO, was ignorant of), instead of Wundewaffen (wonder weapons) like V-I/V-II ICBM's, lithium batteries, first crude-shaped helicopters, and jet-propelled fighter planes used by Luftwaffe.