Law Order
During fights over the Obamacare health-insurance law, a constituent told him to "go back where you came from". The attacks were misplaced. Mr Salazar is proud of his Hispanic heritage, but he comes from a place with deeper American roots than the United States.
One of his ancestors, Juan de Oñate y Salazar, co-founded the city of Santa Fe in New Mexico. That was in 1598, some 250 years before it became American territory (and the best part of a decade before English merchant-adventurers splashed ashore at Jamestown, Virginia).
A laconic man in denims and cowboy hat, Mr Salazar is a fifth-generation Colorado rancher, farming the same corner of the San Luis valley that his great-grandfather settled 150 years ago, just when Mexico ceded the territory to America. As families like the Salazars put it, they never crossed the border, the border crossed them.
But their high desert valley is home to many Spanish-speaking newcomers too.
A demographic revolution is under way. In 1953, when Mr Salazar was born, America's Hispanic population numbered perhaps 3m. It surged after changes in immigration law under President Lyndon Johnson, nearing 9m by 1970. Today it stands at 57m, out of around 321m Americans, and is on course to double by mid-century, when it is projected to be 106m out of 398m.
In the past two decades Hispanic migrants have spread from a few states and cities to places that had not seen big foreign inflows since the days of steam trains and telegraphs. The biggest group, with 34m, is Mexican-Americans. Since 2005 this has prompted Mexico to open five new consulates, from Little Rock, Arkansas, to Anchorage, Alaska (lots of Mexicans work the perilous Alaska crab fisheries).
Hispanics are transforming the definition of what it means to be a mainstream American.
During the roughly 200 years from the presidency of George Washington to that of Ronald Reagan, whites of European descent consistently made up 80-90% of America's population. By the time of the 2010 census, the proportion of non-Hispanic whites (for simplicity's sake called whites hereafter) was down to 64%. Some time around 2044 it is projected to fall to less than half.
Some conservatives would retort that most Hispanics are white. They argue that the creation by federal bureaucrats in the 1970s of a new box on forms turned hard-working migrants into an artificial new race, trapping them in a ghetto of grievance politics and government welfare.
But that is too glib: for generations Hispanic-Americans were whites on paper only, denied equal access to everything from schools to restaurants or town cemeteries.
More broadly, it is white decline that makes today's demographic revolution so remarkable. America has twice before witnessed European migration waves that were proportionately even larger when measured against the population at the time: once in the 19th century and again at the start of the 20th century.
Those new Americans came to be seen as respectable, over time, as they assimilated towards a majority culture rooted in what were explicitly called Anglo-Protestant ideals: self-reliance, rugged individualism, thrift and hard work. Yet now that white majority is on course to become a minority.
This will touch every aspect of public life, from politics to pop culture. Every year around 900,000 Hispanics born in America reach voting age. Neither party should imagine it will own their votes in perpetuity, but Republicans have the most work to do.
In the 2012 presidential election Mitt Romney, the Republican candidate, got nine in ten of his votes from whites, whereas Mr Obama won eight in ten of the votes cast by minorities. If the Republicans want to catch up, party hardliners will have to stop taking extreme positions on immigration. Hispanics are unlikely to listen to messages about jobs or health care from candidates who are also proposing to deport their mothers.
Business is waking up to the rise of Hispanics. Joe Uva, chairman of Hispanic enterprises and content at NBCUniversal, a big media company, is fond of telling fellow executives that with a combined purchasing power of $1.1 trillion, if Hispanic-Americans were a country they would rank 16th in the world.
A giant reason to be optimistic about the rise of Hispanics is that they are making America much younger. The median age of whites is 42; of blacks 32; and of Hispanics 28. Among American-born Hispanics, the median age is a stunning 18.
As other parts of the rich world face a future of ageing, shrinking populations, Hispanics are keeping American schoolyards full of children and replenishing the supply of future workers. Since about 2011, white and non-white babies have been born in roughly equal numbers. White women already have fewer children than needed to replace their parents. Hispanic women's fertility rate has dropped a lot, but at an average of 2.4 children it is still above replacement level.
In a recent book, "Diversity Explosion", William Frey of the Brookings Institution, a think-tank, makes an impassioned call to celebrate America's new demographics. In just a few years, his numbers show, there will be as many whites over 65 as white children. Among non-whites, children outnumber the old by four to one.
Take away Hispanics and other fast-growing minorities, and America's numbers look like those for Italy, a country full of pensioners with a shrinking labour force. As things stand, however, America's working-age population is expected to grow at a healthy clip.
How to double without trouble
It is important not to be Pollyanna-ish about the challenges ahead. If in 2050 America's Hispanic population were to look the same as today's, only doubled in size, a great demographic adventure might end badly.
For now, young Hispanics are more likely than whites to drop out of high school and less likely to complete degrees. Adult Hispanics are half as likely as whites to work as managers or professionals. Fewer of them own their homes, and many were clobbered by the 2008 financial crisis.
Lots of migrants move north to escape drug cartels and violence, but America's proximity to poor, patchily governed countries to its south is a business opportunity for criminals, too. In 2013 the National Gang Intelligence Centre, a government body, estimated that Mexican transnational crime organisations "partner with" 100,000 street-gang members in Chicago alone.
Immigration sceptics commonly point to another question mark that seems to hang over Hispanics. Previous immigrant groups typically saw progress with each passing generation, but Hispanic numbers have a habit of stalling or even heading backwards. American-born children of Hispanic immigrants tend to be less healthy than their parents, have higher divorce rates and go to jail more often.
Jump from migrants' children to their grandchildren, and studies have shown academic results slipping in the third generation. Conservatives fret about "downward assimilation". Academic texts have asked, "Is Becoming an American a Developmental Risk?"
Some see such indicators as proof that foreigners from an alien culture have created a new underclass that must be pushed back. Such fears are overblown: many trends are heading in the right direction, albeit slowly.
This report will visit schools working in innovative ways to improve Hispanic high-school graduation rates and to reduce teenage pregnancies. Many more Hispanics are enrolling in college--and still more would seek degrees if conservative politicians looked to the long term and changed state laws that make the children of unlawful migrants pay much more than their American classmates for a public college education. When one in four children in public schools is Hispanic, economic self-interest alone should prod states to get them ready for the 21st century.
This report will show how some Republicans in Tennessee, a conservative state, are debating pragmatic changes.
Alas, in other states, Tea Party zealots are leading a charge in the wrong direction. Texas used to stand out among conservative states for a businesslike approach to immigration. But in 2014 a dismaying number of Texas Republicans ran for election vowing to repeal a far-sighted 2001 law granting subsidised college tuition fees to students resident in the state, regardless of their legal status.
Steve Murdock of Rice University, a former boss of the US Census bureau, recently published a paper warning Texans that Hispanics are not getting enough advanced degrees and qualifications to replace highly educated whites retiring from their state's workforce. By 2050, his study predicts, Hispanic workers will outnumber white ones in Texas by almost three to one, but without a change in education policy the state will be poorer and less competitive.
The idea of a permanent Hispanic underclass needs to be treated with caution.
In a 2011 study, Brian Duncan of the University of Colorado, Denver, and Stephen Trejo of the University of Texas at Austin argued that the theory of downward assimilation in the third generation may rest on a statistical quirk. People who still call themselves Mexican-American at that point are often less educated and less fluent in English than their better-assimilated cousins, notably the children of mixed marriages, who may no longer identify themselves as Mexican. That makes the numbers for Hispanics look worse than they are.
Nativist panic-mongering about a Hispanic "invasion" has helped to skew public perceptions. Many Americans vastly overestimate the incidence of illegal immigration.
A survey in 2012 by Latino Decisions, a pollster, asked non-Hispanics to guess the percentage of undocumented Spanish-speaking immigrants. The average guess was one in three. The real figure is one in six.
And fresh immigration as a cause of Hispanic population growth was overtaken in 2000 by Hispanic births in America. Of the 17m Hispanic children in the country, some 93% are native-born citizens. Even if a glass dome could be placed over the country, ending all immigration, and every undocumented Hispanic were to be rounded up and deported, tens of millions would remain.
As it happens, the chances of immigrants without papers being sent back have recently diminished.
In June 2012 Barack Obama announced that the federal government would not deport certain undocumented migrants who arrived in America as children, a move that could cover up to a million young people. In November last year Mr Obama extended the scheme to shield about 4m parents of citizens and permanent residents, though his action is now being challenged in the courts.
Grey v brown
The Hispanic population's youth should be celebrated, but poses one grave political risk: a clash with elderly whites. The baby-boomer generation, now beginning to retire, remains an overwhelmingly white cohort.
The alarm was sounded in an essay in 2010 by Ronald Brownstein, "The Gray and the Brown", predicting a generational confrontation between grey-haired oldies, bent on preserving benefits that favour them, and multi-ethnic, brown-skinned youngsters wanting more spending on day care, schools and colleges.
Mr Frey agrees. It is telling, he suggests, that states with the harshest anti-immigration laws often have predominantly white old folk living alongside highly diverse children (in Arizona, for example, 83% of the over-65s are white, whereas 58% of the children are non-white).
Calm logic should prod older Americans to welcome well-educated young taxpayers of any colour. But in politics culture matters just as much as logic.
Even different generations of Hispanics can clash, as John Salazar has witnessed in Colorado. During an attempt to pass a comprehensive immigration reform in Congress, he was berated by Mexican-American constituents whose families had been in his valley "for ever". They asked him why he was trying to help the mojados (wetbacks)--a pejorative for Mexicans supposed to have swum across the Rio Grande.
The San Luis valley, a quiet, deep-rooted spot, is a good place to start discovering how Hispanics will change America in myriad ways--and how the country will change them, offering reminders that Hispanics are among America's oldest as well as its newest residents.
Mr Salazar's ancestors did not much benefit from being the first non-Indian settlers in the valley once white, Mormon incomers started to arrive in the 1870s. Mexican-Americans were deemed overly fond of alcohol, indifferent to education and unworthy to hold most local offices.
"When I was growing up, the Anglos held every position. Every now and then you'd get a Spanish judge," Mr Salazar explains, without rancour.
A great-uncle briefly served in the Colorado legislature, but was ruined by the Depression in the 1930s. Family lore holds that banks foreclosed on supposedly unreliable Mexican ranchers while sparing Anglo neighbours. Decades later, when the future congressman was a boy, he was beaten for speaking Spanish in school grounds.
America offers far more opportunity now. John Salazar, raised as one of eight children on a 52-acre (21-hectare) farm without electricity, recently retired as his state's agricultural commissioner. He oversees family holdings totalling 4,000 acres. His younger brother, Ken Salazar, was the first Hispanic senator for Colorado before becoming President Barack Obama's first interior secretary.
Mr Salazar has a keen sense of history. He proudly shows off some riverside land, silver with frost and sheltered by cottonwood and willow trees. Bank managers took it from his great-uncle almost a century ago, but he recently bought it back. "The most beautiful place in the world," he says.
He is more interested in the future, explaining his plans for the ranch and pondering what immigrants might do if they are brought out of the shadows. New ideas are "what makes our country strong", says Mr Salazar. It is a very American remark.
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