European Union: Key Moments
Photo: Wojtek Radwanski/AFP/Getty Images
A constitution for Europe was signed by the EU's then-25 members in 2004. The last major change to the constitution came about in 2009 when the Lisbon Treaty went into effect. It streamlined the running of the EU and established a full-time president and foreign minister for the union, but some (like these protesters) argued the changes would centralize the EU to its detriment.
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