I can't believe you actually believe this. Different languages in most European countries. Different customs and traditions. Vastly different tastes in cuisine. Vastly varying levels of wealth/poverty. etc.
Languages, yes. They are different. Cuisine? Not so much. Mediterranean diet is more or less the same across southern Europe. Italians, Greeks and Spanish for example have a diet based on olive oil.
Other similarities. Legislation. Most laws passed from the EU are sooner or later adopted by member states. Sports. Football is prevalent all over Europe. Architecture. Neoclassic movement is all over the place. Music, see how many similarities exist between composers of classical music during centuries. Science, CERN is the largest collaboration of scientists in the world. And the list goes on.
In US if you go from New York to Texas you're in a different universe altogether.
>> 72% of Europeans are Christians.
There are no "Christians" in Europe. You actually have Catholics, Protestants, Orthodoxs and a bunch of others. And those guys have been killing each other for very long time. The "Christianity-Version" of each region is actually a very fundamental property explaining those many differences (political parties, welfare systems, work ethics etc.) in Europe (which you claim don't exist).
Using the link you provided there is also this quote:
>> "Eurostat's Eurobarometer opinion polls showed in 2010 that 49% of EU citizens did not believe in God."
Source? I doubt this. Secularism is quite high in Europe and I think their is also quite a high muslim population.
>> IMHO there are more similarities between European countries than between US States.
I can't believe you actually believe this. Different languages in most European countries. Different customs and traditions. Vastly different tastes in cuisine. Vastly varying levels of wealth/poverty. etc.