Citizenship and civil rights
The first section formally defines citizenship and requires the states to provide civil rights.

Section 1. All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.

This represented Congress's reversal of that portion of the Dred Scott v. Sandford decision that declared that African Americans were not and could not become citizens of the United States or enjoy any of the privileges and immunities of citizenship. The Civil Rights Act of 1866 had already granted U.S. citizenship to all people born in the United States; the framers of the Fourteenth Amendment enshrined this principle in the Constitution in order to stop the Supreme Court from ruling it unconstitutional for want of congressional authority to pass such a law, or from a future Congress altering it by a bare majority vote.


Citizenship and the children of legal and illegal immigrants

The provisions in Section 1 have been interpreted to the effect that children born on United States soil, with very few exceptions, are U.S. citizens. This type of guarantee—legally termed jus soli, or "right of the territory"— does not exist in most of Western Europe or the Middle East, although it is part of English common law and is common in the Americas.

The phrase and subject to the jurisdiction thereof indicates that there are some exceptions to the universal rule that birth on U.S. soil automatically grants citizenship. Two Supreme Court precedents were set by the cases of Elk v. Wilkins 112 U.S. 94 (1884) and United States v. Wong Kim Ark 169 U.S. 649 (189. Elk v. Wilkins established that Indian tribes represented independent political powers with no allegiance to the United States, and that their peoples were under a special jurisidiction of the United States. Children born to these Indian tribes therefore did not qualify for automatic citizenship under the Fourteenth Amendment. Indian tribes that paid taxes were exempt from this ruling; their peoples were already citizens by an earlier Act of Congress.
In Wong Kim Ark the Supreme Court held that under the Fourteenth Amendment to the U.S. Constitution, a man born within the United States to foreigners (in that case, Chinese citizens) who were lawfully residing in the United States and who were not employed in a diplomatic or other official capacity by a foreign power, was a citizen of the United States.

Under these two rulings, the following persons born in the United States are not "subject to the jurisdiction [of the United States]", and thus do not qualify for automatic citizenship under the Fourteenth Amendment:

Children born to foreign diplomats;
Children born to enemy forces in hostile occupation of the United States;
Children born to Native Americans who are members of tribes not taxed (these were later given full citizenship by the Indian Citizenship Act of 1924).
The following persons born in the United States are explicitly citizens:

Children born to US citizens;
Children born to aliens who are lawfully inside the United States (resident or visitor), with the intention of amicably interacting with its people and obeying its laws.
The Court in Wong Kim Ark did not explicitly decide whether U.S.-born children of illegal immigrants are "subject to the jurisdiction of the United States" (it was not necessary to answer this question since Wong Kim Ark's parents were legally present in the United States at the time of his birth). However, the Supreme Court's later ruling in Plyler v. Doe 457 U.S. 202 stated that illegal immigrants are "within the jurisdiction" of the states in which they reside, and added in a footnote that "no plausible distinction with respect to Fourteenth Amendment "jurisdiction" can be drawn between resident aliens whose entry into the United States was lawful, and resident aliens whose entry was unlawful."
This implies that the U.S.-born children of illegal immigrants qualify for citizenship under the Fourteenth Amendment.Some legislators, reacting to illegal immigration, have proposed that this be changed, either through legislation or a constitutional amendment. The proposed changes are usually one of the following:

The child should have at least one parent who is a U.S. citizen.
The child should have at least one parent who is a U.S. citizen or permanent resident The child should have at least one parent who is lawfully present in the United States.
For example, Representative Nathan Deal, Republican of Georgia, introduced legislation in 2005 to that would provide that U.S.-born children would be "subject to the jurisdiction of the United States" (and therefore entitled to automatic citizenship under the Fourteenth Amendment) only if at least one parent were a U.S. citizen or permanent resident. [2].

Similarly, Representative Ron Paul of Texas has introduced a constitutional amendment that would deny automatic citizenship to U.S.-born children unless at least one parent is a citizen or permanent resident [3].

Neither of these measures has come to a vote