One of the fears about immigration reform seems to be that it would lead to a flood of new citizens and change the cultural (and electoral) map. But that's overblown.
While a "pathway to citizenship" would be opened to the over 11 million immigrants estimated to be living in the U.S. without papers, for instance, including more than 6 million Mexican immigrants, it would be taken by far fewer.
That is, if the past is any indication of the future. Many legal immigrants in the U.S., who are already eligible to apply to become citizens, don't do so. Mexican immigrants, for whom this is most common, often elect to become legal permanent residents instead (with the right to work but not to vote).
"Nearly two-thirds of the 5.4 million legal immigrants from Mexico who are eligible to become citizens of the United States have not yet taken that step," write researchers at the Pew Hispanic Center.
The reason most don't is because of the hurdles involved or lack of interest.
The number of undocumented immigrants who would become citizens under the new immigration law would be in the millions, not tens of millions. In a melting pot of over 300 million, that's adding just a pinch, and a welcome one at that.
A bigger debate is likely to be had is over how the U.S. should treat family members.