The older theories, for instance, simply ignored risk, and assumed that workers could move seamlessly between jobs. It was assumed that the economy was at full employment, so that workers displaced by globalization would quickly move from low-productivity sectors (which had thrived simply because foreign competition was kept at bay through tariffs and other trade restrictions) to high-productivity sectors. But when there is a high level of unemployment, and especially when a large percentage of the unemployed have been out of work long-term (as is the case now), there can’t be such complacency.