Although an amendment cannot be unconstitutional, (an amendment becomes a part of the constitution) the hard and fast accepted concept that anybody born in the United States is automatically a citizen can be challenged. Here is the wording of the amendment which is now a part of the constitution.
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.
“All persons born in the United States” is very clear. That does not leave much room for argument. However the following phrase “and subject to the jurisdiction thereof” does create ambiguity. If the parents of the born person are citizens, that fact would negate any ambiguity, but what if the parents are not citizens of the United States, or what if the parents are in the United States illegally. Under either situation, a strong argument can be made that the person born is the United States is not subject to the jurisdiction of the United States but is subjected to the jurisdiction of the nation of which the parents are citizens. The argument is even stronger for those who are here illegally.
When the Fourteenth Amendment was ratified in 1868, the United States did not limit immigration in any manner. Anybody that came into the United States was here legally. It could be argued if you are in the United States legally, you are subject to the jurisdiction thereof, but anybody in violation of the laws already would not qualify.
The ambiguity will need to be decided because the decision should have and hopefully will have a major implication on the immigration policy of the United States in the future. The Marxist/Progressives will argue that the current understanding be confirmed. The Marxist/Progressive Party has many potential votes at stake, unless they get their wish through a different process that all people, citizens or not, dead or alive, are able to cast as many votes as the individual wishes.
The debate over the Fourteenth Amendment has very significant meaning to the long term viability of the United States being a free nation or becoming the totalitarian state it will under Marxist/Progressive domination.