Because they needed a leader even if he was a complete screwup like Obama.
http://en.wikipedia.org/wiki/John,_King_of_England
John (24 December 1166 – 19 October 1216), also known as John Lackland (Norman French: Johan sanz Terre),[1] was King of England from 6 April 1199 until his death in 1216. Following the battle of Bouvines, John lost the duchy of Normandy to King Philip II of France, which resulted in the collapse of most of the Angevin Empire and contributed to the subsequent growth in power of the Capetian dynasty during the 13th century. The baronial revolt at the end of John’s reign led to the sealing of the Magna Carta, a document sometimes considered to be an early step in the evolution of the constitution of the United Kingdom.
“a complete screwup like Obama.”
I wonder about that. He is now a lame duck and doesn’t care because he does not have to run for political office again. It may be that things are going exactly as he and/or his puppet masters want/s them to go.