Destroy their cities, destroy their food & supply sources, drive them to the ends of the Earth then kick them off the side. Obliterate them so badly they will never recover. Enemies like terrorists in the Middle East hide wherever they can, so destroy anywhere and everywhere they can hide. Burn them out of their holes, then execute them.
What enemy could be worse than destroying your own people, land, and property? Even if an enemy were to overpower us, we could still resist using guerrilla warfare. What do you think the people the U.S. are fighting are currently doing? Anything is better than practically committing mass suicide as a military tactic.
There are other ways to defeat an enemy besides using the Scorched Earth Policy. The assets that are burnt could be useful to the military forces using this policy. Also, I do not believe that this policy should be used in its home territory. Only in extreme circumstances could I see this policy being acceptable to enforce but as of 1977, it has been banned by the Geneva Convention and should stay that way so that tyrant leaders cannot use this against those who oppose them.
No, it would have to be a really horrible situation to even consider this. Perhaps if you had been nuked you could do this, but this often involves numerous civilian deaths. We need other options that are either more surgical or that involve talking. Unless you are in immediate danger of being destroyed, this is not necessary.
A scorched Earth policy is akin to total war, and it would be against the Geneva Conventions. Absolute devastation just breeds hatred, and that hatred turns into terrorism eventually. People will seek revenge. War is never a good option, and it needs to be avoided at all costs. If it has to happen, the parties involved should not engage in war crimes.