When i say if the usa wasnt involved i mean they didnt enter the war, no lend lease act, and no aid of any sort. In this poll the japanese didnt atack pearl harbor and did not go to war.
Personally i believe that they would be able to for the following reasons
1, the nazis wouldnt have there factories being bombed, and would be able to keep the german war machine rolling.
2, The soviets wouldnt have all the supplies, guns, tanks, ect. That they would have recieved from the usa, thus decreasing their ability to wage war.
3. The british, although they may still be able to keep the nazis from invading, would no be able to take any major offensives to retake the mainland.
4. The nazis would have more time and supplies to develope and produce more sophisticated weapons, such as the atomic bomb, jet aircrafts, and missles.