What Would The World Be Like If D-Day Never Happened?

What if we lost? What if the Invasion of Normandy, one of history's greatest military gambles, had been repulsed by the Nazis?

Historian Douglas Brinkley told INSIDE EDITION it could all have been very different.

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"If D-Day failed, which it could have, we would have had the sad spectre of a revitalized German empire starting to build nuclear capacity," said Brinkley. "Fascism would have dominated the world, not democracy."

For those first agonizing hours of the invasion, Brinkley said, the success of D-Day hung in the balance.

Brinkley explained, "For the hours when this was happening, nobody knew what was really transpiring, but by the end of the day Franklin Roosevelt, our president, was able to hold a ceremony in the White House under a tree and say, 'We did it.""

Saving Private Ryan is a realistic and grim testimony to the nightmare the allied forces had to endure on the beaches of Normandy, Brinkley said.

"Steven Spielberg did a masterful historical recreation," said Brinkley. "It's almost stunning, the amount of detail he put into that.

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"We may not be there having a conversation if it wasn't for the heroism of those 160,000 allied troops that stormed the five beaches of Normandy," said Brinkley.

This Story Originally Ran in June 2014

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