This is a red herring - there's no law against untruthful political advertising. Such a law, broadly enforced, would likely be unconstitutional and how do you suppose that you enforce it? Also, if that was the law, it wouldn't be up to corporations to determine what is true and the responsibility would fall between the politicians and the regulatory body that decides what the truth is. That sounds to me like a totalitarian nightmare but I suppose YMMV.
I don't know why it would be any different constitutionally from false advertising in any other context. It's not a crime per se, but false advertisers can be held civilly liable for misleading consumers, and individual consumers can sue false advertisers, as can the FTC on the public's behalf (presumably it would be the FEC instead, but work similarly). The court system (so, presumably a jury) decides whether or not it's false.
Civil liability is an entirely different matter altogether but what's problematic about false advertising isn't that the claim was false, but more that you're breaking a promise. This isn't about free speech, but more about an implicit contract being violated. Political speech, on the other hand, is explicitly what the freedom of speech as a right is about.
Either way, I don't believe anyone would claim that in case of false advertisements, the responsibility falls on the publisher of ads, not the advertiser. It's not generally possible to evaluate the claims made in advertisements - if I were to say, something I'm selling will work for 10 years and will offer replacements if it breaks in the next 10 years, how would the ad publisher know if I would honor the claim several years later?
If there were rules governing political ads in social media, they would look very much like Facebook's policy. At least TV ads (which are more tightly regulated due to the use of radio spectrum, which are public goods) are regulated as to force TV stations to air even political ads they deem untruthful:
TV networks are required to air even untruthful ads as not to run afoul of regulations governing political ads. It's also likely that campaign laws requiring all political ads to be true would be unconstitutional.
Either way, the very fact that the Elizabeth Warren campaign is promoting a fairly blatant falsehood (and many people are happy to parrot a false talking point in the name of truth) is a symptom of the same problem that would force any reasonable entity to make the same decision Facebook just did. Truth isn't very popular, especially in politics and people (on every side of most political issues) would lose their mind if falsehoods were strictly banned.
I think it’s important to mention that Elizabeth Warren is displaying a blatantly false ad to illustrate this exact point: she thinks that it’s ridiculous that Facebook is airing obviously false ads and has no accountability.
The blatantly false part I'm talking about isn't "Mark Zuckerberg is endorsing Trump" which everyone understands to be the obviously false statement, but the subsequent argument that is still being repeated here that "If Trump tries to lie in a TV ad, most networks will refuse to air it."
A whole bunch of comments here are along the lines of: how come Facebook isn't required to abide by the rules that other media companies have to follow? But this is the exact opposite of how things are - small media companies can adopt whatever standards they want, but the broadcast networks have to air even false political advertising, because these types of regulations are more about protecting fairness and free political speech than about the truth. This is an example of Facebook subjecting themselves to the highest possible standards, instead of making arbitrary editorial decisions that smaller actors can get away with.
It's not the same high standard when they allow targeting of specific people and groups highly vulnerable to bullshit with no one else included who might identify it as such.
How would this be any different from advertising on certain shows or talk radio that peddle huge amounts of BS and are almost exclusively consumed by gullible people?
Again, the point is that the standards followed by broadcast TV are higher than the standards followed by, random media companies that aren't regulated. And what Facebook is doing here aligns closely with how public institutions that are held to the highest standards operate. The general principle regarding the freedom of speech is that the closer you are to being a public institution, the more open you ought to be in terms of the types of speech you accept.
So the criticism here isn't merely wrong, it's exactly backwards.
I can freely choose what shows, radio stations and other media I see, and see the same ads as their audience. In the case of targeted ads, I can't move from demographic to demographic as I please, so some campaigns are inaccessible to me.
To me, that opaqueness separating one filter bubble from the next is an important quality. It may raise the effectiveness of propaganda campaigns significantly.
That can't possibly be not true. The state has not and can not have any role in determining what is "true", if only freedom of speech has any value. As soon as the state gets to decide what is "true" and ban speech on that basis, freedom of speech is destroyed. In the USSR, there was a section in the criminal code banning "knowingly false statements defaming the state and the social order". Obviously, people who were punished under this section were ones that said anything that the communist regime didn't like, and their statements always were "knowingly false", because the same communist regime decided what is false and what is not. I don't think the US should follow this example. That's why the Constitution exists and why the First amendment is the first one. Because it's that important. Yes, the price of it is somebody can say something you don't like. You'll survive it.
Defamation, for example, is not protected by the First Amendment, and deciding whether some information is true or not is crucial to determining whether it constitutes defamation.
This is irrelevant - there are all kinds of speech that are generally accepted to be outside the scope of free speech. Political speech that includes false claims does not fall under that and never has. If taking down "false speech" was something the US government can easily enforce, we'd make China look like a shining beacon of freedom. And the proper recourse to such speech is the court, not poorly paid and overworked social media moderators.
Also, it's important to keep in mind that the Trump ad in question does not make claims that are easily proven to be false - they are merely BS claims that are entirely unsubstantiated. I don't think they'd be taken down even if a rule against false claims existed and was properly followed. There's no evidence given for such claims, but not all claims without evidence are false.
The regulations exist in the exact opposite direction as you claim - TV networks are required to air even untruthful ads as not to run afoul of regulations governing political ads, which means Facebook's policy is closely aligned with the actual regulations as they exist.
Also, most newspapers at least online are are outsourcing part of their ad placement to third-party ad tech companies so I'd be shocked if there was any editorial control.