However, the Doctors Without Borders protocol should not apply to visitors like Liberian victim Thomas Eric Duncan who might enter the U.S. for a prolonged family visit and share close quarters with many other people, including children. Of course, such visitors should not be confined to a tent with a portable toilet, either; it would behoove federal and state authorities to arrange for facilities that are more humane and comfortable, not to mention sanitary.

In contrast to Christie’s injudicious use of quarantine, there are others who seem to reject it altogether, and in dismissing it, sometimes display a lack of insight or knowledge. Over the last month or two, I have heard comments like this dozens of times: “Influenza kills thousands of people every year, but we’ve only had one (or two, or three, or four, or five) cases of Ebola in this country…” This is naive at best and disingenuous at worst. All epidemics start with a few cases, and although many (or even most) potential epidemics are arrested or controlled before they actually become epidemics, it’s not very predictable at the outset.

This is even true for the current Ebola epidemic in Africa, which was initially thought to be just another periodic outbreak. When there are sporadic cases of any contagious disease, it is impossible to know how far it might spread. If quarantine is to be effective, it should be instituted early, not after the disease has gone out of control. We haven’t needed to impose a quarantine for many years, partly because the communicability and mortality rates of various outbreaks did not justify it. In that respect, we’ve been lucky in the U.S. over the last several decades; public health measures and medical technology deserve a lot of credit, too. But “decades” is a very short period of time in human history, a history marked with multiple devastating epidemics and pandemics. Remember that it has been less than 100 years since an influenza pandemic infected 500 million people and killed as many as 100 million.