Isn't it cruel to keep cats outdoors?

Cats are allowed outdoors, and if they would confine themselves to gardens, there would be few problems. However, since cats tend to want to expand their roaming territories, the results of those roamings are exposure to dangers such as traffic, roaming packs of dogs, and other predators, including the human kind. Those dangers are not exclusive to the U.S.

I can't say that it's "okay," or even preferable, to let them roam freely; but there are some safe alternatives, like garden-type enclosures, so that cats can enjoy the best of both worlds.