This is changing in the United States. It was originally set up to encompass all of the freed slaves who did not originate their citizenship in the US. It has since been abused, especially by Mexican citizens, to cross into the US illegally and then have a child to establish a 'foothold' for citizenship and residency. There is legislation proposed to incorporate a change in the law, so that any illegal who has a child will not have the 'citizenship at birth' right, only legal residents. Debate lies around both what to do with those in the country on visas (but not residing) and the fact that there is a 'voice of concern' among the hispanic population.