shocked that the US Pledge of Allegiance has been declared unconstitutional
The UK has an established religion: Christianity. That wouldn't be my choice, but in practice it is never, ever actually a problem. It always amuses me that the US are so proud of their separation of Church and State, and yet US politics is riddled with religion in a way which UK politics simply is not. If you bluntly ask Tony Blair or the Queen whether they believe in God, both will say yes; but neither will go out of their way to mention religion in speeches aimed at the general population.
Responding to specific points: the reference in the US constitution to "an establishment of religion" probably meant a specific technical meaning of "establishment", that of a state-sponsored church -- in the sense that the Anglican church is the "established religion" in the UK. And I read somewhere that "Congress shall make no law..." was a formula meaning "We'll leave it to the individual states to decide", not "There shall be no such law anywhere".
Religious schools: it's never been quite clear to me what "humanist" means, but I'm all for it if it means that that which de-humanises is evil. That certainly includes religious schools. I wouldn't mind them if they offered a more broad-based education: Christianity one year, Hinduism the next, Islam, Judaism, and so on. That way such schools might function as an inoculation, and prevent children contracting full-blown religion if they were exposed to contagion later in life. But I suspect none actually function like that, instead just acting as recruitment and indoctrination camps. Supporters of political parties or football teams don't get to send their kids to indoctrination camps in order that they grow up with their parents' arbitrary biases and blinkerednesses, and I don't see why supporters of religions should either.
Peter