As one of the last decisions the Supreme Court handed down in this year's term, they upheld the concept of "birthright citizenship" enshrined within the Fourteenth Amendment. Barely.

The stunning thing wasn't the ruling, which was expected. The truly stunning thing is that the decision was partly 6-3 and partly 5-4. It should have been at least 7-2, with the only dissenters being Samuel Alito and Clarence Thomas (who always vote the way Republicans want them to vote, no matter how clear the legal evidence is on the other side). Honestly, the decision should really have been 9-0, since the case is so cut and dried. Having it only 6-3 (or 5-4) shows that too many conservative judges are complete hypocrites when they swear up and down that they are "originalists" or "textualists" who only take into account what the Constitution (or any amendment) meant by the people who drafted it. Whenever that lofty principle becomes inconvenient in a case, too many of the conservatives just start making stuff up instead of reading the clear and unequivocal language of a law or an amendment.

Which is where we should begin this discussion, in fact. Here is the full text of the relevant section (the first) from the Fourteenth Amendment:

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.

The first sentence is the one that was being fought over in this Supreme Court case. Donald Trump tried to wipe this sentence out with an executive order, which was declared unconstitutional and void by the court.

Trump's contention was that the second clause of the sentence ("and subject to the jurisdiction thereof") meant something radically different than the obvious plain meaning of the words. Who is "subject to the jurisdiction" of the United States of America? Well, for starters, every single person who is currently inside the borders of the U.S.A. Can absolutely anyone get arrested for committing a crime in America? Yes. Yes, they can. Can they be charged in court, tried, and sentenced for committing a crime? Again: yes, they can. That is the dictionary definition of "subject to the jurisdiction thereof." Period. You'll note that I said: "every single person," and not: "every citizen." Because everyone is subject to the same laws. Citizens, immigrants, tourists... anyone physically present within the country for any reason at all can be arrested, tried, and jailed for committing a crime.

It doesn't matter what your legal status is. Except for one very specific exception: diplomats and their families. Anyone with "diplomatic immunity" (a diplomatic passport, in other words) is actually not "subject to the jurisdiction" of America, even when they are here. They could murder someone right in front of a cop and the only penalty they would face would be expulsion from the country. They would not be arrested or tried in court or sentenced, no matter what crime they had committed.

The correct reading of the amendment becomes even more obvious when you read the last sentence in Section 1, because it forbids even the states the ability to "deny to any person within its jurisdiction the equal protection of the laws." Again: not just a citizen, but "any person." The framers of this amendment were very precise -- this section alone differentiates in different places between "all persons born... in the United States," and "citizens of the United States" and "any person" within the country's jurisdiction. Those words were carefully chosen to mean precisely what they say they do. There is no looseness to them at all.

Trump wanted to change all of that so the amendment somehow read: "and who have expressed some degree of loyalty to the United States," instead of just: "subject to the jurisdiction thereof." Only people with green cards or other long-term legal status to be present in America (tourists and students and people on various other kinds of legal visa wouldn't qualify -- only people on the path to citizenship). And certainly not undocumented immigrants.

As the court ruled today, Trump is wrong. However, this case means a great deal to him. He signed the executive order on his first day back in office. For the first time ever in American history, he actually attended part of the oral arguments held before the Supreme Court as a sitting president. And apparently, he's not giving up even now. After the ruling was announced, Trump posted on social media:

The Supreme Court upheld Birthright Citizenship, which is too bad for our Country, but we can easily make it up in Congress through Legislation, with the support of the President, that has now been determined during this process. No long and unwieldy Constitutional Amendment is necessary! Congress should start TODAY to work on ending expensive and unfair to our Country, Birthright Citizenship. They will have my Complete and Total Support!

This is, of course, just as wrong. A constitutional amendment would be necessary to change the meaning of the Fourteenth Amendment. Congress does not have the power, through legislation, of overturning an amendment. They just don't -- even if the president offers them his "Complete and Total Support!"

Sure, some sort of crackpot ultraconservative bill could be written that attempts to redefine the Fourteenth Amendment, but even if it did manage to pass a Republican Congress (an open question), it would wind up back at the Supreme Court eventually, and they would rule exactly as they ruled today.

At least one Republican senator admitted this today. Senator Mike Lee posted to social media his reaction, which was entirely correct and proper: "The long fight for a constitutional amendment begins now." Lee is correct -- that is the only route to changing things that is constitutionally valid. But the bar is so high for a constitutional amendment that it is likely never to advance at all.

Today was a win for the United States Constitution. It was even a win for the conservative "textualist" and "originalist" legal school of thought. The words in the Fourteenth Amendment mean precisely what they say they mean, period. This was so painfully obvious that even a majority of the Supreme Court justices had to agree. It is more than a little disappointing that the ruling wasn't 7-2 or even 9-0, but at least enough of them to prevail admitted the inescapable legal reality of those words.

-- Chris Weigant

Follow Chris on Twitter: @ChrisWeigant