The Buddha sat under a tree until he found enlightenment, then told us we could do it too. His idea was for us to experiment and experience for ourselves. And Buddhism's direct, experiential access to the sacred proves useful to those on other paths. It's not exclusive. There's no contradiction being Moslem, Christian, Jew or atheist, and practicing mindfulness.
Priests attend Buddhist retreats, and corporate executives can be found there too.
And mindful poetry ripens at the interface of American and Buddhist traditions.