Alien and Sedition Acts: Questions

The Alien and Sedition Acts were a response to an internal immigrant threat that never materialized. Was there a period of history when they were needed?
The Alien Enemies Act is the only one of the four Alien and Sedition Acts to stay on the books. Is there any value in it? Should any of them have stayed on the books? If so, which and why?
When the Alien and Sedition Acts were enacted, the concept of judicial review (the Supreme Court determining if a law is Constitutional or not) had not really been established. So were the Alien and Sedition Acts Constitutional or not? Does that matter if they are needed?
The Naturalization Act increased the number of years for an immigrant to be naturalized. How long should it take? Why?
Should immigrants from friendly nations be treated differently than ones from unfriendly nations? What determines unfriendly? Do we have to be at war with them, or is any diplomatic tension enough?
Of all the Alien and Sedition Acts, the Sedition Act is the most blatantly unconstitutional. Yet we accept limitations on our First Amendment rights every day. What sort of limits should there be? Any? Why or why not?