The correct policy needs to keep potential carriers of the Ebola virus out of the general population of American citizens.
F'rinstance, someone arriving from the Ebola Hot Zone should not be permitted to leave his residence 5 days after returning to the USA, to ride three subway trains, go to a bowling alley, go to a restaurant, go to a second bowling alley, and take a taxi home.
BOTTOM LINE: Voluntary quarantine does not work; people do not always do the right thing.
1. A ban on permitting anyone from the affected areas to fly into the USA would accomplish the proposed isolation most effectively and at the lowest cost. Such a ban would also relieve commercial airlines flying into the USA from the potential hazard of contaminated aircraft. [If/When an aircraft were to prove to have been contaminated, DonDiego would expect air travel plans to drop rather precipitously.]
2. A quarantine for a sufficient time to guarantee the traveler is not infected would also accomplish the goal of keeping infected persons out of the general population. This would have to be at least 21 days, although recent comments from medical personnel suggest 42 days may actually be necessary.
2.a. The present "protocol" permits the traveler to self-monitor himself at home. This has proven unacceptable. [And if a presumedly intelligent, well-intentioned physician would violate his self-monitored quarantine, DonDiego would expect a less-informed or less well-meaning traveler to be even more likely to violate such a voluntary procedure. And someone who believes himself to be infected and flies to the USA for the purpose of receiving medical treatment, would have no reason to quarantine himself.]
2.b. Given the failure of self-monitoring, DonDiego suggests anyone arriving from a Hot Zone should be really quarantined and kept away from the general population. As already stated a ban on flying into the USA would accomplish this with little cost, . . . but it would allow travel elsewhere than the USA. Other countries would presumedly do whatever they think best. Otherwise, a secure quarantine facility, or facilities, would be required whether on the periphery of the Hot Zone or within the USA; think something like Ellis Island with spartan accommodations and medical facilities on-site.
3. Although not strictly applicable to the Ebola Epidemic, prohibiting unauthorized border crossing into the USA would serve generally to also keep diseases from arriving. [Apparently the massive arrival of "youths from Central America" in the Summer of 2014 was accompanied by, f'rinstance, an infusion of scabies, chicken pox, MRSA staph, and other infections.]
4. None of the above precludes anyone from flying into a Hot Zone to, f'instance, provide medical aid or supplies of any sort. DonDiego would encourage anyone so inclined to help out those in need.