How does a patently false claim from the lips (or tweet) of Donald Trump get legitimized to the point where many Americans think it's true?In one word--Television.Television is how most Americans get their news. Six out of every 10 Americans say it's their main source of news. Perhaps more relevant, for those over 50 that figure rises to more than seven out of every 10. For all the hoopla about the Internet, only about four of every 10 Americans regard it as their main news source. It tends to be preferred by those below 30, an age group that is far less likely to vote than those 50 and over.Television viewing is also America's most popular leisure activity (apart from sleeping). The average person watches about 5 hours a day. That's about 1800 hours a year or about a third of a person's total non-sleep life. Despite all the claims by critics that television is a wasteland, television viewers seem to be satisfied with what they find on TV. While there is a huge diversity of television fare available, they obviously trust the medium to provide programming that they find desirable. If what they watched wasn't consistent with their values and beliefs, they wouldn't spend all that time glued to their sets.The advertising industry capitalizes on this trust relationship. Last year it spent $73 billion to advertise products on television. The industry knows that public opinion is easily influenced by mass media messaging through television. As political attack ads regrettably attest, whether the message is true or not is irrelevant. The industry knows that if you repeat a message a sufficient number of times, many will be persuaded of its authenticity. More importantly, if the message comes with the voice of authority as, for example, in the case of a presidential tweet, the likelihood that it will be believed is greatly increased.The rise of Putin's popularity among Americans is an excellent demonstration of the latter. According to Gallup, before Trump's adulatory comments, only 13% of Americans had a favorable view of the Russian leader. Since then, that figure nearly doubled--to 23%. More striking, among Republicans who historically have been tough on Russia, his favorability has increased almost threefold--from 12% in 2015 to 32% today.The shift happened during a time when Putin invaded Crimea, started a war in eastern Ukraine that has killed 10,000 Ukrainians, and has unleashed the Russian war machine on civilians in Syria to maintain the blood soaked dictator (the civil war has claimed 450,000 victims) Bashar al-Assad in power.Given what a nasty piece of work Putin is, it is truly disturbing to see how easy it is for Trump to galvanize the power of mass media messaging to serve his interests. Perhaps many Americans don't know much about Putin. That may help explain their susceptibility to Trump's sweet words about the thug.Trump's accusation that mainstream news outlets deliver fake news to Americans, however, is an entirely different matter.Americans know their news media a lot better than who Putin is. Like other TV shows they watch, they choose news shows they like to watch. It's certainly not the ones with fake news.How then does such an obvious lie gain traction among so many Americans? How is this lie elevated to a possible truth? And if it's television as has been postulated, how does that work?Let's look at how this happens.Recently, Fox News produced a poll with a story graphic showing 45% of Americans trust Trump to tell the truth while reporters who cover the Trump administration received only 42% degree of trust.The purpose of the story was to show that millions of Americans agree with Trump--that mainstream news media report fake news. And if mainstream news media delivers fake news, then why would anyone believe anything they report about his multitude of other lies. It's all fake news! By destroying the messenger, Trump destroys the truth. In the court of public opinion, Trump's lies begin to acquire the trappings of truth.Except that's not what the poll question asked.The question was: "Who do you trust more to tell the truth--the Trump administration or the reporters who cover the administration?"Even in these early days there have been strong differences of opinion between some members of the Trump administration and Trump's comments during the campaign on important matters like Putin, Russian aggression, and support of NATO. The Trump administration includes individuals of character like James Mattis as Secretary of Defense, Lieut. Gen. McMaster as National Security Advisor, and Rex Tillerson as Secretary of State.  All have a reputation for telling it like it is.So if respondents believe Trump is a liar but also believe the three appointees or others in the administration would not compromise their reputations by lying, then they would have reason to trust the Trump administration to tell the truth. When it comes to responding to the Fox question on trust, it puts these respondents in the same company as those who believe Trump tells the truth more than reporters.How many of the 45% who say they trust the Trump administration more to tell the truth belong to the former group? How many belong to the latter? Combining the two in the same response category as the Fox poll does makes the question useless. It overstates the number who believe Trump is truthful.Measuring public trust in news media is complex. Reporters not trained in the art of interpreting opinion polls have not done a good job in addressing this complexity. Research suggests that Americans trust the news outlets they regularly watch and distrust those they don't. Poll questions that ride roughshod over these distinctions tend to produce misleading results. They helped foster the "fake" notion promoted by Trump and Fox News -- that Americans do not trust the mainstream news media.But it wasn't enough that the Fox poll question was biased. The headline in the story is misleading as well. It states: " Fox News Poll: Voters divided over trusting Trump or the media". It's the Trump administration, not Trump that voters are divided in trusting. The story graphic showing these misleading results repeats this fakery.In all of this manipulation, Fox's intended message is clear: The public trusts Trump more than the reporters.In spite of the question bias, these poll results were cited again and again on Fox News to show that a plurality of Americans trusted Trump more than the news reporters. These poll results were rehashed on other mainstream news networks as well. No one really looked closely at the conflation problem.By the end of the news cycle on the story, the TV message was that more Americans trust Trump than the reporters. It's worth noting that while a Trump tweet on the topic has approximately 26 million followers, the reach of television approaches 300 million Americans. For the Trump lie it was mission accomplished.Fox plays a pivotal role in giving credibility to Trump lies. It is a hugely influential cable news network. It gets about three times as many viewers as CNN, its main competitor. It provides the staple news diet for millions of Americans every week. At the same time it functions as the propaganda arm of Donald Trump and the Republican Party.This puts it in an untenable conflict of interest: Is it reporting the news or is it reporting the propaganda?Regrettably, those who control Fox News like chairman Rupert Murdoch and the previous chairman, the disgraced Roger Ailes, prefer propaganda to news. Both men have a long-standing personal relationship with Trump. Fox News is there to serve Trump's interests, truth be damned.Too often Fox sabotages the other mainstream news outlets by not challenging Trump's lies. Instead it promotes these lies as truthful, frequently repeating them every night, week after week to its audiences. Over time, Fox viewers are psychologically conditioned to believe them to be true.The justification for this from Fox is that it's balancing liberal points of view with conservative ones. But a lie is neither liberal nor conservative. It's simply a lie.In choosing propaganda over factual news reporting, Fox betrays the most sacred trust of journalism--to identify and report the truth as best it can. It betrays its employees who believe their job is to be responsible journalists. It betrays the audiences that watch its programs, believing what they hear is true. Lastly, it betrays the American people by dividing the country with its misleading messages and thereby undermining its political institutions.Oleh Iwanyshyn has been involved in public opinion polling since the mid-70s, first with the Institute for Behavioral Research at York University, then the Canadian Broadcasting Corporation and more recently with ViewStats Research, a company he cofounded in 1997.  He writes on the role of public opinion polls in matters of politics and public policy.  His articles have appeared in iPolitics, The Hill Times, and National NewsWatch. For more, see his blog poll stuff.