Isnt blocking the building of the ground zero "mosque" unconstituitional?

ima real new yorker (not arab) and im also a real american (never stepped foot outside the country) and i also feel sypathy for those 911 victims, but i also believe in the vision our founding fathers had for this country such as freedom to practice religion that is why im interested to know what you people think about this issue. majority of people dont want the mosque to built there, but wouldn't blocking it be hypocritical of U.S?