Whether the false information is politically or financially driven, junk news is now part of the media ecosystem.
And, in the fight against the sprawling web of hoax sites and conspiratorial blogs, the law is largely powerless, experts have said.
Fake stories like Clinton selling weapons to ISIS and running a child-sex ring or Ireland accepting American "refugees" fleeing Trump have been seen and shared by millions of people in recent months.
Dr Damian Tambini, director of the media policy project at the London School of Economics (LSE), said the unprecedented number of such sites was a "huge and far-reaching problem that cannot be dealt with in existing legal categories".
He said: "The law has never had to distinguish between what is true and false before, that has always been given over to journalistic ethics and verification.
"That is the big, profound change we are seeing today.
"The law has an indirect role, but not in a way that would apply to Macedonian, boiler-house production sites."
He said legal challenges could theoretically apply if posts were defamatory or incited hatred or violence but many obstacles stand in the way of litigation even getting off the ground.
Dr Tambini brought up the 'pizzagate' episode, in which fake news led a man, Edgar Welch, to the Comet pizzeria in Washington DC where he fired a rifle.
Welch went to the restaurant to "self-investigate" spurious online reports that Hillary Clinton and her aide John Podesta were running a clandestine child prostitution ring from the basement.
Dr Tambini went on: "The 'pizzagate' shooting in DC may be a clear case where the owners were defamed, you just had to scroll through the comments.
"There were clearly causes for legal action, but whether the threat of prosecution is a reasonable and effective deterrent is another question entirely."
He raises the case of the Robin Hood Airport tweet bomb joke, which saw Doncaster man Paul Chambers found guilty of sending a threatening tweet only to have his conviction overturned.
Dr Tambini added: "The case asked difficult questions, such as when should prosecution go ahead? Is there real malice? Are there real victims? And, is prosecution likely to succeed?"
Top libel lawyers cost hundreds of pounds per hour, and that could all be wasted wildly chasing a remedy to an explicitly false story on a hastily put-together website.
And there are myriad problems of enforcement and jurisdiction if the publisher is halfway across the world or untraceable.
The accountability of a proper newspaper or publisher is just not there.
Ian Walden, a professor of information and communication law at Queen Mary university, said prosecutions would be much harder in the US than the UK because of strong first amendment rights to free speech.
He added: "Ofcom has the power to revoke broadcasting licenses, like it did with Press TV and threatened to do with Russia Today (RT).
"But we don't regulate the internet in the same way so the threshold is very different.
"Essentially, we're going to have to accept this big grey noisy area of rubbish."
Both experts agreed children needed to be taught how to read more critically to deal with the new media ecology.
A recent Stanford study found a "stunning and dismaying" consistency to young people's' ability to verify internet info.
It tested middle school, high school and college students and found: "When it comes to evaluating information that flows through social media channels, they are easily duped."
Prof Walden added: "In schools, we don't teach people how to read things in the media, for example the different rules covering TV and newspapers.
"The 'marketplace of ideas' concept has always required the ability to read critically and a desire to get to the truth and other things many people choose to avoid or just don't have.
"Journalism is in a bit of a perfect storm at the moment."