Reuters/Stefan WermuthOn March 25, European Union leaders celebrate the 60th anniversary of their founding treaty, a central pillar of the structure set up in the aftermath of World War II to solidify peace, prosperity and partnership in Europe. Over the last 60 years, the EU (and its predecessors) has served as an essential partner: for example, by enhancing economic opportunity for companies in Europe and increasingly supplying vital foreign assistance and diplomatic support to help solve international problems.