The United States either should:
A. Use standard time year-round.
B. Use daylight time year-round.
Switching between the two causes all Americans to go through the trouble of changing all of their clocks twice per year. This is particularly annoying in the modern day since almost every electronic device has its own clock that requires adjustment. While many modern devices now can automatically synchronize themselves from central time sources, adding such a capability to every device is not practical and might not be desirable.
The practice also makes it more confusing when dealing with other countries (or even with Arizona or Hawaii) where daylight saving time is not observed or where it is observed on different dates.