To the jurisdiction of what government is that child subject? What does it mean to be subject to the jurisdiction of a government?
An illegal alien, or a child born within the borders of these United States to illegal aliens, who commits a crime within the borders of these United States will theoretically face trial for that crime in a United States or State court. The trial will be conducted according to United States and State law. Does that make the illegal alien or child thereof subject to the jurisdiction of these United States?
“Does that make the illegal alien or child thereof subject to the jurisdiction of these United States?”
Territorially, yes.
Nationality, no. Foreign nationals are routinely brought up on charges and tried. Their nationality becomes an element of the laws applied and the disposition of their trial.
The authors of the 14th amendment make it clear that they meant subject to the total and complete jurisdiction of the USA. John Bingham even said what I have been using as my tagline since 2011.
"of parents owing allegiance to no other sovereignty."
Not so fast. Mexico intervenes on behalf of it’s citizens because Mexico has jurisdiction.
A child inherits the citizenship of parents. Child born on US soil to Mexican citizens has Mexican citizenship even if we give it US citizenship by statute as well.