Europe Needs a Two-Tier Solution to Move Past Brexit

The European project is in a funk. Talk of ever-closer union has been silenced by the U.K. decision to quit the European Union. The long-term solution lies in acknowledging that while some European countries want nothing more ambitious than a free-trade area, others should get on with building a full-fledged United States of Europe.

A coalition of the able and willing -- the former qualification being much more important than the latter -- should retain the euro but cut loose the currency's weaker members. All of the architecture needed to make a success of the common currency can then be built, including a full banking union, common bond issuance, a centralized Treasury function with an empowered finance minister, and properly coordinated fiscal policies.