Former President Jose Maria Figueres of Costa Rica has a saying I like: “There is no Planet B” — so we’d better make Plan A work to preserve a stable environment. I feel the same way about America these days. There is no America B, so we’d better make this one work a lot better than we’ve been doing, and not only for our sake. When Britain went into decline as the globe’s stabilizing power, America was right there, ready to pick up the role. Even with all our imperfections and mistakes, the world has been a better place for it. If America goes weak, though, and cannot project power the way it has, your kids won’t just grow up in a different America. They will grow up in a different world. You will not like who picks up the pieces. Just glance at a few recent headlines.