The whole world war was poisoned by most of the world, and in order to defeat fascism, all the countries of the world united to form the prototype of the United Nations. In World War II, the United States, the Soviet Union and China all paid huge sacrifices, but if you want to say the number one hero, it is estimated that it will cause a lot of controversy.
In World War II, the Soviet army suffered the most casualties, the U.S. army paid the highest cost, this is the two number one meritorious candidates, as for China, Britain and France, China paid a huge sacrifice of personnel, in the Far East to resist the pace of Japanese aggression, with backward weapons and equipment to resist the attack of a powerful enemy, can also be regarded as hard work. Britain won the Battle of Britain, and its colonies of Australia, Canada and India contributed to the victory. France's contribution was rather limited and it largely withdrew from the scramble.
If you asked this question after World War II, it would definitely be the Soviets. Because the Soviets were defending against the most powerful Germans, in terms of strength at the time, no one was an opponent of the Germans except the Soviets. Basically, all scholars in the world believe that the German attack on Poland was the starting point of World War II, and the German army was also the strongest of the three Axis powers. The Soviets were able to withstand the German offensive, which in itself was a miracle.
Later, the Pearl Harbor incident occurred, and the United States officially joined World War II, accelerating the pace of victory in World War II. But all this presupposes the sacrifice of the Soviets. It was the Soviets who survived the most difficult years of 1941 and 1942. This is an achievement that no one can erase. Every battle fought by the Soviets cost hundreds of thousands of casualties. There was no way to do it, the German army was really very powerful at that time, if you do not use the superiority of troops, the Soviet army is difficult to hold out. Only the Soviet army has such a strong willpower and can always adhere to the confidence of victory in the huge personnel consumption.
After the confrontation with Germany, there was also Japan in the Far East. With 700,000 Japanese Kwantung Army entrenched in the northeast, this was the last obstacle to Japan's surrender. It was also the Soviets who launched the August storm and bulldozed the Kwantung Army in a week. If it is handed over to the US military, it will not be possible to achieve it without a year and a half.
If I had to find a number one hero, I would like to give this credit to the former Soviet army, who brought the hope of victory to all mankind in the most dangerous moment. What do you think?