According to a recent survey, the modern device Americans rank No. 1 in making their lives better is the microwave oven, which was introduced 30 years ago this autumn. Nearly 90% of American households now have microwaves, up from only 10% in 1977. The increase has been so inexorable that it's easy to envision a time when there are few enough nonmicrowave households in this country to be listed individually, branded for all to see as people who have never witnessed the miracle of a potato baked nearly instantaneously before their eyes. Our household, alas, could be on the list.
On...