Related Clues:
- What this puzzle's theme commemorates
- Word next to an arrow, maybe
- Possible result of a gunshot
- 'Saving Private Ryan' occasion
- Boot up
- With 21-Across, begin from scratch
- 24 hrs. on Omaha Beach
- Outset
- June observance
- Machine button
- It was also called Operation Overlord
- Decisive '40s event
- Pivotal WWII time
- Turn a key, perhaps
- 'It's now or never' time