I'm just going to go through a few passages to lay out the facts so that the racist cult that has been gaining steam in Reformed circles has no excuse before God on judgment day.
1. The popular idea amongst racists that the mark of Cain was God making people black has no support in the text. And how exactly would his lineage look after marrying a white woman and having mixed children who then went on to marry white people? Black people don't come from Cain. This was an attempt by racist groups to stigmatize black people as murderers. It's purely eisegetical.
2. The popular idea amongst racists that Ham is cursed by being made black is not only without support in the text, it actually negates what the text says. Ham isn't cursed. Hence, all of his descendants aren't cursed. Only Canaan is cursed. Hence, only Canaan's descendant's are cursed, and they aren't black. The Canaanites are Middle Eastern. We know this from archaeology and from their depictions in Egyptian literature as the "Asiatics." Either way, the Hamites who may have made up Africa aren't the cursed ones. Given all of this, it's clear that the curse isn't making them black. That's not even a part of the curse in the text so to say that changing their skin color is part of it is, again, eisegetical.
3. Moses married an Ethiopian woman and the attempts to say that she probably belonged to the "other" Cush doesn't fit the context of Miriam and Aaron becoming made about it. First, it should be clear, they're not mad about racial differences per se. It's clear in the context that they are mad that Moses might be thinking he's a king, and they don't like him lifting himself up over them. Like all people who envy others in authority, they're arrogance detectors and so accuse him of arrogance because he married an Ethiopian. Why would this have anthing to do with him lifting himself up over them? Because Ethiopian women, both in appearance and in wealth, were often seen as exotic and women that only kings and extremely rich and powerful men in other countries would marry. This is consistent with their reaction. It's not because he married more than one wife, since that was common among lower class men too. It's not because she's a foreign woman because that was also common and he had already done that with Zippora who was a Midianite. Marrying a black woman signified wealth and power, and they didn't like him flaunting his power over them since they too were prophets of God.
4. Those who emphasize externals (skin color) over culture (the most important element being religious culture and values) don't have the Spirit of Christ in them. God looks at the inward person over the outward one. Blind men look to the outward so they worry a whole lot about how that cup looks and clean it constantly to hide the fact that cleanliness and filth matters far more on the inside. The Pharisees hated Christ on this point, as his dirty disciples didn't wash their hands before they ate and they could not stand anyone claiming to be godly doing such a thing. These people care much about appearances and think it's a tragedy if everyone were to return to a single color. You know, like Adam and Eve were, or weren't.
And that brings up an interesting point. Were Adam and Eve both the same skin color? Is it possible that God actually made them genetically diverse? In fact, isn't it probable and even biblical to say that they had all the genes of all the races in them? If that's the case, aren't they a case of every race being married as God's original intent to every race? This brings us to another popular suggestion that isn't supported by the text.
5. God made the races when he divided the nations at Babel. Um, no, He didn't. He split people off linguistically. There is nothing in the text that supports the idea that He made them all different races. In fact, we know that it isn't true, as there are a lot of nations created here that are still made up of the same races. Also, God didn't make new humans at Babel, so every human being has the same genetics he had from Adam and Eve, which means that everyone could have taken upon the characteristics of everyone else given the same environment, time and genetic combination through procreation. The borders are given so that these people who speak the same language can have a homogenously linguistic society, not because Macedonians and Greeks are different races of people. And this isn't even talking about the entire world but the entirety of the land in the Ancient Near East which have a total of three groups involved, those who came from Shem, those who came from Ham, and those who came from Japheth. The lands mentioned are just within that sphere.
6. The fact that God tells them they can marry other women who are slaves or captured in battle from other nations means he has no problem with interracial marriage. What he does have a problem with throughout the Bible is interreligious marriage, daughters of a foreign god. He also allows men from other nations, like Caleb for instance, to marry Israelites wives. The host of Egyptians and Nubians and other slaves who went out from Egypt with Israel are never prohibited from marrying Israelite women as long as they were non-Israelite Israelites, religiously speaking.
7. This brings us to the final point I want to make here and that is that interracial marriage is never forbidden or even frowned upon implicitly in Scripture, and I would argue, it is actually encouraged implicitly through the principle of the incest laws. The further one gets away from one's own genetics, the healthier and stronger humanity becomes. The closer one gets, the more defects are multiplied. Now, of course, this can be accomplished with white people marrying white people and black people marrying black people but my point is that, if anything, it would more a sin to marry closer to one's genetic pool than further away from it. Obviously, it's only a stated sin to have relations to close within family units but the principle would show that the opposite has no similar principle governing it.
Like all cults, this one takes verses out of context to support it and then tries to mangle the texts that speak against it so that they silence the voice of God in opposition to them.
I get that our culture is emotion and reactionary and most people condemning the movement have no credit since they react by their own brainwashing rather than with exegesis, but this movement really is unbiblical. It's not simply a virtue signal or cultural indoctrination. This is actually something our culture gets right because of its remnant Christian influence. What our culture gets wrong is the blending of religious races, sons of God and daughters of the devil, or vice versa, and the reverse racism and genocide they practice. But an overreaction is what the devil wants here. As I've said before, he doesn't lead conservative Christians astray by telling them to attend Drag Story Hour or ordain homosexual bishops. He drags them away from the importance of the gospel and the inward and eternal trajectory of our sights by causing us to overreact with another falsehood and immoral sentiment.
I'm sure those forbidding marriage and the eating of certain foods were reacting against rampant sexual immorality and the celebrations of foods in honor of idols. Nonetheless, Paul also calls this the teaching of demons, and that's what we need to understand.