The most common and most likely answer to this crossword clue is the 10 letter word GOOSE-STEP
I've seen this crossword clue in The Guardian
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More clues leading to the result GOOSE-STEP
Buddy explains!

The straight part
We know that "The way Nazis made progress?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case the way nazis made progress? = goose-step.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GOOSE-STEP mean?
GOOSE-STEP noun- A style of marching in which the feet are lifted high in the air in front.
- To march with a goose-step.