There is a key distinction.

Furthermore, the issue, based on your responses, is not that I "don't know what the Polish contribution was", but that you seem to have an odd definition of "decisive". A "decisive" contribution is one that changes the outcome. Not hastens an outcome, but changes it. It affects the DECISION of the war, not its cost to those fighting it.

So, NO, something that reduced the length of the European war by two years is NOT, in any way, a "decisive" contribution. It is a significant contribution, but clearly not decisive. It didn't change who won.

Furthermore, given how large the Red Army was (35 million Soviets were in its service at one point or another during the war) and how sophisticated its industrial production was getting, the Soviets could have destroyed the Wehrmacht without significant Allied contributions, and the Enigma decoding played only the most minor role on the East Front.

If Germany did not receive the oil it needed from Romania, I doubt that Operation Barbarossa would have gotten as far as it did. It wasn't until the fall of the Ploesti oil fields in 1944 that Germany's oil supplies started to suffer. Hitler got the oil he needed until then.

I repeat: the underlying assertion that led to this entire thread is little more than a lot of backslapping to ease the perpetually bruised ego of the Poles. Hell, that whole Guardian article is little more than such backslapping. So the cavalry didn't charge tanks, but just armored cars and mobile infantry. The Poles still had a terrible defense plan and lost even though they knew exactly what Germany was throwing at them.