Stopping Mexican or Muslim immigration will not make you safe.
If your target audience has a flawed ideology, then your propaganda doesn’t have to lie to them. The lie, in some sense, has already been embedded and only needs to be activated.
and also 2012’s “How Lies Work“:
You can’t be blamed for the false information, irrational prejudices, and ugly stereotypes that already sit inside people’s heads, waiting to be exploited. So good propaganda contains only enough false or repulsive information to leverage the ignorance and misinformation that’s already out there.
In other words, the central lie in an effective propaganda campaign is the one you never explicitly say. It’s out there already, sitting in the minds of your followers, so you just need to allude to it, suggest it, and bring it to consciousness in as many ways as you can. Your target audience will hear it, and afterwards most will believe you said it. But because you aren’t saying it in so many words, it’s immune to fact-checkers, and you barely need to defend it at all. Let PolitiFact and NPR carp all they want about the details of your speech. They can’t touch your central point because it’s not really there.
The explicit promise of Trump’s speech is that he will make the country safe, not just eventually after doing the long, hard work of changing public policy, but almost instantly.
The crime and violence that today afflicts our nation will soon — and I mean very soon — come to an end. Beginning on January 20th 2017, safety will be restored.
So if you have been hiding under your bed, you’ll be able to come out next January.
This is the kind of sweeping pledge that ordinarily would be met with embarrassed laughter. It’s as if Barack Obama had promised not just that he would get health insurance for millions of people before he left office, but that all the uninsured would be covered by the time he got done with his inaugural address.
Imagine if Hillary Clinton were to promise this week in her acceptance speech that poverty and unemployment “will very soon come to an end, beginning on January 20”. I’m voting for Clinton, but I’d laugh at that promise. I might give her credit for good intentions, but systemic problems like poverty and unemployment are obviously beyond the power of presidential wand-waving.
So are crime and violence, but for some reason Trump’s audience was not laughing. Why not? What in the worldview of Trump or his followers makes it credible that “the crime and violence that afflicts our nation” can be ended “very soon” by presidential action?
If you don’t already know, the speech will not tell you. In fact, if you don’t already understand the big lie that the speech is based on, you will have a hard time making sense of it at all: The whole hour-plus speech will seem like a grab bag of loosely related anecdotes and factoids, many of which are false.
Since the speech never lays out that central claim, I will: The main threat to your personal safety is the street crime and terrorism brought to America by Mexican and Muslim immigrants.
If you hold that (false) fact in your head, the speech hangs together. Many of its details are still untrue, but at least it begins to tell a coherent story.
Decades of progress made in bringing down crime are now being reversed by this administration’s rollback of criminal enforcement.
Here we begin to see how crime and violence might come within the president’s power, and what could instantly change on Inauguration Day: President Obama doesn’t enforce the law; President Trump will.
But what laws has President Obama stopped enforcing? Murder laws? Rape laws? No: In the American law enforcement system, those crimes are almost entirely the responsibility of state and local officials. But there is one kind of law that falls almost entirely under federal enforcement: immigration laws.
Nearly 180,000 illegal immigrants with criminal records, ordered deported from our country, are tonight roaming free to threaten peaceful citizens. [See endnote 1.] The number of new illegal immigrant families who have crossed the border so far this year already exceeds the entire total of 2015. They are being released by the tens of thousands into our communities with no regard for the impact on public safety or resources.
Trump goes on to mention several individuals (some of whom previously spoke to the Convention) who are victims of violent crimes by Hispanic immigrants. The existence of such stories should not surprise anyone; it wouldn’t be hard to compile anecdotes of crimes by any reasonably large group of people, like the left-handed or the red-haired. What makes these immigrant-crime stories more than just talk is the unspoken implication that they illustrate some kind of trend: an immigrant crime wave.
But in reality, the anecdotes are just anecdotes: There is no trend. Immigrants, both documented and undocumented, commit fewer violent crimes per capita than American citizens. They are responsible for such a tiny amount of violent crime in America that, if Trump does manage to make them all disappear somehow, your safety will be virtually unaffected. In short: There is no immigrant crime wave.
One more thing you should notice in that quote: how effortlessly Trump glides from immigrant criminals to immigrant families, and from public safety to public resources. Since there are so few violent immigrant criminals, the white voters Trump is targeting are very unlikely to be their victims or to know any of their victims. But many white families send their children to school with Hispanic children whose immigration status they don’t know. (Most are either legal immigrants or American citizens.) The point of lumping families and criminals together is to imply that those Hispanic children are a threat to your white child. 
In addition to crime, Americans are afraid of terrorism. This is another part of “the crime and violence than today afflicts our nation”. The federal government has a key role to play in disrupting 9-11 style plots, in which terrorist groups conspire to kill large numbers of Americans. In recent years it has been doing that job very well (or else the threat is not a large as we thought immediately after 9-11). No plot remotely comparable to 9-11 has been carried out.
But it’s not clear how much the feds can do to stop lone-wolf terrorists like Dylann Roof (a native-born American white Christian who bought a gun legally and used it to kill nine members of a black Charleston church) or Omar Mateen (a native-born American Muslim of Afghan heritage who used legal guns to kill 49 people in a LGBT nightclub in Orlando). For every American who carries out an attack, countless others fantasize about one in some vague way, and may even discuss their fantasies on social media. We can’t lock them all up.
But Trump again ties this threat to immigration.
Lastly, and very importantly, we must immediately suspend immigration from any nation that has been compromised by terrorism until such time as proven vetting mechanisms have been put in place. We don’t want them in our country.
My opponent has called for a radical 550 percent increase — think of this, this is not believable, but this is what is happening — a 550 percent increase in Syrian refugees on top of existing massive refugee flows coming into our country already under the leadership of president Obama.
She proposes this despite the fact that there’s no way to screen these refugees in order to find out who they are or where they come from. I only want to admit individuals into our country who will support our values and love our people. 
The only Muslim immigrant tied to a recent terrorist act is Tashfeen Malik, half of the couple who killed 14 people in San Bernardino last December. (Her husband was native born, as was the shooter in Orlando. So were the assassins who killed police in Dallas and Baton Rouge.) She came to this country on a fiancée visa, not as part of any refugee program or by sneaking across a border. So even in that exceptional case, building a wall or refusing to help Syrian refugees would have made no difference. There is no Muslim refugee terrorism problem.
The real American terrorist threat is overwhelmingly homegrown, and includes white supremacists, violent anti-abortion activists, and Bundy-and-McVeigh-style anti-government militiamen, in addition to native-born ISIS-inspired jihadists. Nothing Trump has proposed will do anything to make you safer from them.
The speech then segues from fear of violence to economic fears, and again immigrants are at fault:
Decades of record immigration have produced lower wages and higher unemployment for our citizens
Two things to notice here: First, in TrumpWorld those low wages have nothing to do with the decline of unions, which has diminished workers’ negotiating power. They also have nothing to do with the decades-long decline in the inflation-adjusted minimum wage, which Trump wants to see continue. In short, anything real the government could do to improve the lot of low-wage workers has been pushed aside in order to scapegoat immigrants.
Second, and perhaps even more important, adjectives like illegal or undocumented have vanished: All immigrants are the problem now. Having raised fear with anecdotes of violent crime by undocumented Hispanic immigrants and implications that Muslim refugees are responsible for our terrorism problem, that fear is now channeled into anxieties about jobs and money, and targeted at everyone who comes to America, including those who come legally hoping to find legal jobs, as my ancestors did 150 years ago.
So now that I’ve laid out the larger structure of Trump’s speech, and the unspoken big lie that pulls it together, I invite you to go back and read his text end-to-end, preferably one of the versions annotated by fact-checkers. If, as you read, you bear in mind that there is no immigrant crime wave and no Muslim refugee terrorism problem, I predict that the speech’s whole theme will fall apart. You will be left with a collection of cherry-picked statistics and random falsehoods, which the fact-checkers can handle quite well.
 The Chicago Tribune adds context to this number:
The actual crimes committed by this group are not documented, however, so Trump cannot easily claim that all of these illegal immigrants “threaten peaceful citizens.” A significant percentage of their crimes involve immigration violations and nonviolent offenses, according to historical records.
In other words, we’re more likely to be talking about paper crimes, like faking a driver’s license or other ID, rather than the violent crimes Trump is implying. And that stands to reason: If you’re in this country without legal status, you’re trying to hide from authorities, not call attention to yourself by assaulting someone.
 Obama’s most obvious non-enforcement of immigration laws is that he is not deporting the Dreamers, those undocumented immigrants brought to the U.S. as young children, who grew up in the U.S. and know no other country. Trump’s rhetoric also makes them a threat to your child.
Today, Dreamer Astrid Silva addresses the Democratic Convention. I invite you to watch her and do your own threat evaluation.
 Fact-checkers can catch all the individual lies here: We are admitting only a tiny number of Syrian refugees, so even a 550% increase will still be just a drop in the bucket. (About 5000 since October 1, and 1682 in the year before that. For comparison, Germany already had about 100,000 Syrian refugees a year ago, and is talking about admitting 500K a year. There are about five million Syrian refugees worldwide — 11 million if you count the ones displaced to other parts of Syria.) We are vetting them extensively. So far, the refugees who make it through the U.S. vetting process are responsible for zero acts of terrorism.
The “support our values and love our people” line is a dog whistle to Islamophobes. Newt Gingrich spelled it out on July 14:
Let me be as blunt and direct as I can be: Western civilization is in a war. We should frankly test every person here who is of a Muslim background, and if they believe in Sharia, they should be deported. Sharia is incompatible with Western civilization. Modern Muslims who have given up Sharia, glad to have them as citizens. Perfectly happy to have them next door.
As other people have explained in more detail, sharia is not the same as terrorism, and asking Muslims whether they “believe in” sharia is like asking Jews if they believe in the laws of Moses. At some level of interpretation, of course they do; but that doesn’t necessarily mean they intend to kill adulterers or gay men. Gingrich’s implication — that we can accept Muslims in America only if they don’t take their religion seriously — ought to offend any person who does take religion seriously.
BTW: Cutting off Syrian immigration means turning away Syrian Christians, who are being wiped out in some areas and whose relief is a special project of many Evangelicals. But if Trump makes an exception for them, then he’s back to having a religious test for letting people into the U.S.