Transcript for Emmanuel Macron becomes the youngest leader of France since Napoleon

And to France tonight. Getting ready for a new president now, after a high stakes election being watched by so many right here in the U.S. Would French voters halt the wave of nationalism? Marine LE pen, who take to take France out of the eu, the euro and nato, conceding defeat. Celebrating victory, the -year-old centrist, Emanuel macron. ABC's Terry Moran from Paris tonight. Reporter: A night to remember in Paris. Emmanuel macron, joined by his wife and chief adviser Brigitte, basks in his victory. At 39, the youngest leader of France since Napoleon -- Merci, mes amis! Reporter: This morning, already taking center stage, joining incumbent president Francois Hollande in a solemn ceremony to mark the end of World War II in Europe. In choosing macron, a pro-european union centris, French voters decisively rejected the far-right nationalism of marine lepen, who president trump practically endorsed, calling her the "Strongest" candidate. The margin -- a whopping 66-34. Lepen was dancing last night after conceding defeat, but her campaign, which stoked fears of terrorism after hundreds have been killed in recent attacks here, nevertheless, failed miserably. Her defeat, a crushing blow to the right-wing nationalist movement in Europe and perhaps elsewhere. Tonight, there's an investigation into that massive computer hack on the macron campaign, which did not help lepen, but may have backfired. David? Hacking there in France, as well. Terry Moran with us from Paris. Terry, thank you.

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