The US constitution and the bill of rights are based on classical liberal ideas, like inalienable rights, the consent of the governed, secularism, etc.
Not at all. Those ideas were formed in a time when they were not the norm. State religion is about as conservative as you can get, it has existed for all of human history, and was the default until very recently. When the US constitution was adopted it was a progressive change. However, yesterday's progressivism is always today's status quo.
