The statue of Christopher Columbus, tall atop a rococo column in the spacious Madrid plaza, gazed off toward the New World as more than 750,000 Spaniards gathered in the square and streets and parks around it. Chanted the crowd: "NATO no! Bases out!"
That rally and a dozen others like it that have been held in recent weeks in Spain are part of a heated debate preceding a referendum over whether Spain should remain a member of the North Atlantic Treaty Organization. The vote takes place this week, and preballot polls show the pro-NATO forces losing in a close contest.
At...