I am an American, not by accident of birth but by choice. I voted with my feet and became an American because I love this country and think it is exceptional. But when I look at the world today and the strong winds of technological change and global competition, it makes me nervous. Perhaps most unsettling is the fact that while these forces gather strength, Americans seem unable to grasp the magnitude of the challenges that face us. Despite the hyped talk of China's rise, most Americans operate on the assumption that the U.S. is still No. 1.

But is it? Yes, the U.S. remains the world's largest economy, and we have the largest military by far, the most dynamic technology companies and a highly entrepreneurial climate. But these are snapshots of where we are right now. The decisions that created today's growth — decisions about education, infrastructure and the like — were made decades ago. What we see today is an American economy that has boomed because of policies and developments of the 1950s and '60s: the interstate-highway system, massive funding for science and technology, a public-education system that was the envy of the world and generous immigration policies. Look at some underlying measures today, and you will wonder about the future.