Banking is safer under a diversity of regulatory regimes. The banking union proposed by Jose Manuel Barroso, the European Commission president, rests on the assumption that the European authority would maintain the highest standards. Many banking regulators around the world have failed to maintain the highest standards. Some countries' banking sectors remain intact only because of the diversity of banking regulatory regimes around the world.
The European authorities creation of the euro was flawed. It is unlikely that a unified banking regime would be flawless.
I acknowledge The Telegraph's "Debt crisis: Jose Manuel Barroso urges EU to back plans for a banking union" and The Financial Times' "Barroso upbeat as political winds change".