“Whether or not they are assimilating is harder to quantify. Becoming an American is a complex, personal process—the kind of transition that can take a lifetime, even two. A Mexican farmhand with a sixth-grade education takes a different path into the mainstream than an Indian engineer working on an MBA, and the sometimes mind-boggling diversity of today’s immigrants can make it difficult to generalize. What’s more, even when one focuses on one group, it can be hard to assess just how well or how fast they are integrating. Economic success or failure, for example, is reflected in countless and sometimes contradictory statistics, and in today’s polarized immigration debate, any statistical portrait is sure to be controversial. Nevertheless, a lot is known about today’s”