At first, no one took the Brexit vote seriously. Few believed that the British would actually leave the European Union (EU). But the decision has become a reality and Ireland and the rest of the world could be among its casualties.

The EU was originally set up so that the 29 countries of Europe could trade among themselves without custom duties. The union also encouraged free travel with no passport control between countries that had so often gone to war with one another.

Four years ago, in this space, we endorsed Martin J. Walsh for mayor of Boston. The Reporter Newspapers was one of only two city newspapers (The Weekly Dig was the other) to back Walsh in the final election.

This time, as Walsh seeks a second term, we have company. The Boston Globe and the Boston Herald both endorsed Walsh this week, a reversal for both dailies who, in 2013, favored John Connolly, Walsh’s opponent. Last week, Connolly himself endorsed the mayor.