Everyone does it 

I Spy...

Why Allies Watch Each Other

Breathless coverage of the revelations that the National Security Agency (NSA) has been tracking allied foreign leaders aside, spying on allies -- even friendly ones -- is nothing new in international politics. In the mid-sixteenth century, the pious King Philip II of Spain and the pope kept tabs on each other as they prepared for the sailing of the Spanish Armada against Britain. The reason? The pope thought the king indecisive, and the king believed that the pope was hedging his bets.