West's Encyclopedia of American Law | First Amendment

The First Amendment to the U.S. Constitution reads:

Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.

At first glance, the First Amendment appears to be written in clear, unequivocal, and facile terms: "Congress shall make no law" (emphasis added) in contravention of certain religious and political principles. After a closer reading, and upon further reflection, the amendment's underlying complexities rise to the surface in the form of persistent questions that have nagged the legal system over the last two centuries.

What kind of law "respect[s] the establishment of religion"? Does the First Amendment include here only laws that would establish an official national...