The decades-long plan to stitch together countries and cultures into the European Union was ultimately blamed for two crises: mass migration and crippling debt. Together, those events contributed to a wave of nationalism across Europe. In a five-part series this week, we take a look at some of the movements aiming to disrupt the E.U. from within. Guest: Katrin Bennhold, the Berlin bureau chief for The New York Times. For more information on today’s episode, visit nytimes.com/thedaily. Background reading: Before the European Parliament elections last month, Katrin Bennhold and producers of “The Daily” set out on a 10-day trip to find out what Europe means to Europeans today.The results of the elections indicated that the struggle over the future direction of the European Union would only intensify.