legislative intent is non sequitur when the statute or const'al article under consideration is clear and unambiguious. The Const. is replete with ambiguious terms (due process, unreasonable search, etc) but the one you're worked up about is without any ambiguity, it says something clear and simple and therefore means precisely what it says. All of the fervent teeth-nashing and breast-beating will not change the plain meaning of the words used in the article.
I'm reading you loud and clear now. Nevermind.
There's plenty of dispute about what "subject to the jurisdiction thereof" exactly means. Does it mean that arresting authorities in the United States who arrest illegals for crimes committed here DO NOT have to notify the Mexican consulate or embassy of their arrest by virtue of their being "subject to the jurisdiction" of the United States and therefore not subject to any Mexican jurisdiction? Teh government of Mexico is claiming that they must be notified as the arrestees are still Mexican citizens and subject to Mexican jurisdiction. The case of Jose Ernesto Medellin is on the Supreme Court's docket for this term. We'll see.