Paris and Athens — Amid all the philosophical debates over the ideals and obligations of the European Union, Brussels has long counted on support from at least one demographic: youth. 

Young Greeks say they are just as Europe-minded as their peers in Spain, Britain, or Germany. They eagerly take part in the continent's popular Erasmus program for studying abroad and increasingly move to other EU countries for the jobs that are so scant at home.

So why did 80 percent of Greek youth cast a defiant "no" on Sunday against Brussels' bailout plan for the country?

Though they may see themselves as European, Greece's young people also say they've had enough. Polling figures show their distrust of the EU is higher than the average, more so than in other crisis-hit countries in southern Europe – and that could grow if they are kicked out of the eurozone or forced to bear reforms they consider socially unjust and even anti-European.

"Youths don't question Greece's belonging to the EU. They are nurtured to believe that [Greece] is the cradle of Europe," says Maro Pantelidou-Malouta, a professor of political science at the University of Athens. But she adds that anger about the direction of the EU and its treatment of Greece is mounting – and could even become a boon to the extremists in Greece who reject the EU altogether.