More National Anthem Protests Expected on Saturday — in Spain

King Felipe VI of Spain, in green tie, stood for Spain’s national anthem at last year’s Copa del Rey final while Barcelona fans whistled and waved Catalan flags. The protest has become an almost annual event.BARCELONA, Spain — A long hail of whistles and jeers from a crowd numbering in the tens of thousands might not be the most articulate way to express a political opinion, Arnau Pans acknowledged with a shrug. But, in his eyes, it can serve a purpose.

Pans, 24, is a die-hard fan of the soccer club F.C. Barcelona and, like many such fans, an active supporter of the Catalan independence movement. On Saturday, for the fifth consecutive year, Barcelona — the most high profile of Catalan…