Three of the four items are part of the "Lemon test" (as it has been called) that came out of the Lemon v. Kurtzman case.
Legislation concerning religion
1. Must have a secular legislative purpose.
2. Neither advances nor inhibits religion.
3. Must not foster excessive entanglement with religion (on the part of the state).
The original case was about whether teachers who were teaching in private schools that had a religious affiliation could be paid with state funds if they were teaching the same courses taught in public schools, using the public school textbooks and instructional materials.
The Mexican-American war of 1846-1848 was justified in the opinions of many by the idea of "Manifest Destiny", since this held that the US was "destined" to expand to the Pacific Ocean.
