[T]his is also a city where Trump's rhetoric seems divorced from the reality on the ground: Waterloo has made a remarkable recovery in recent years, a transformation to which thousands of immigrant workers have made a major contribution. It's a common story across the heartland, and across the nation.

Many employers here say they long for more, not fewer, immigrant workers, and certainly do not favor the mass deportations Trump espouses. Local politicians of all stripes said the city is a striking example of how an economy can be rebuilt with the help of a community drawn from around the world -- "the most diverse place in Iowa," as one business leader boasts. [...]

Trump mocked his rival Jeb Bush, who is married to a Mexican-born woman and who expressed sympathy for those who come here illegally. "He said, remember, 'They come as an act of love,' right?" Trump told the crowd of about 1,000. "In the meantime, they're killing people."

He also ridiculed the idea that the United States may admit thousands of Syrian refugees, many of whom have fled a civil war that has killed hundreds of thousands of people, suggesting that they might be part of a terrorist army that would be unleashed once they arrive in the United States.

"We know nothing about them," Trump said, "They are not documented. This could be one of the great Trojan horses. This could make the Trojan horse look like peanuts."

Many in the crowd devoured it. Trump supporters at the rally described themselves as either disaffected from the party to which they had long belonged or disillusioned with politics in general.

Many said their disaffection with politics began after Ronald Reagan left office. They said the subsequent presidents were, in effect, of one party, a permanent establishment that doesn't represent them.