Enemy of the states: The Rio Grande's real America

The mighty Rio Grande river forms a natural and increasingly lawless border between the US and Mexico. It's a land of extreme anti-Obama sentiment and the burgeoning Tea Party movement with well-armed vigilantes hunting down desperate migrants
George Sprankle, one of the Minutemen who patrol the US-Mexico border: "I've got seven or eight guns. Before we just had people coming across; now we have drugs, armed men and mules carrying drugs." Photograph: Zed Nelson/INSTITUTE

This is a story about right-wing politics, and a journey along the route of one of the longest rivers of the United States. The river, and the story, starts in the mountains, where the crystal-clear waters of the Rio Grande rise at nearly 13,000ft in the National Forest of Colorado. The Rio Grande then travels 1,885 miles through three American states, forming a natural but highly contentious border that divides Texas and Mexico. By the time it empties into the Gulf of Mexico, the water is polluted, depleted and muddied, rather like the politics of the region.

With the mid-term elections of 2 November approaching, and as anti-Obama sentiment becomes increasingly vocal, a journey along the Rio Grande exposes the growing unrest in right-wing America. In Wheat Ridge, Colorado, north of the Rio Grande river, Phil Wolf has erected a vast billboard in the forecourt of his used-car dealership, decrying President Obama. Towering above Wolf's fleet of four-wheel-drive pick-up trucks, an image of Obama wearing a turban is accompanied by the slogan, "President or Jihad?", followed by "Birth Certificate – Prove It!"

Supporters of the "Birther Movement" claim President Obama was not born in the USA and demand that his birth certificate be made public. "Obama is a fraud and a fake," Wolf tells me. "To me the guy is a radical Muslim. A hundred years ago they would have hung him. In my mindset this guy needs to be done away with. He is not an American. I think he is the enemy." These kind of statements are not limited to the political fringes: a recent poll reveals that a majority of Republicans believe Obama is a Muslim and a socialist who "wants to turn over the sovereignty of the United States to a one-world government".

The anti-tax, anti-government Tea Party movement is both a product and an expression of the current volatility in American politics. Reckless, anarchic and strident, it is galvanising support around the country. In Texas, close to where the Rio Grande ends its journey and disgorges into the sea, the local McAllen Tea Party warns that "revolution is brewing in the Rio Grande Valley": its website calls on members to join their "efforts to stop our country's swift turn toward socialism and, yes, even Marxism" and urges that "we must protect our right to bear arms from the insanity of the Obama administration." Along my route, these sentiments were echoed by many.

When Obama was sworn in as the 54th president of the United States, gun sales increased dramatically in Texas and Colorado. In Texas you are not legally required to obtain a permit to have a gun at home, or to carry one in your car; in Arizona and New Mexico it is legal to carry a handgun openly in public. And as gun owners demand their Second Amendment rights, virulent anti-immigration sentiment along the US border with Mexico is also increasing. Speaking on a Tea Party tour in Arizona, one delegate recently spelt out his plan for dealing with illegal immigration: "Put a fence in and start shooting."

The Border Fence Project – America's patchy attempt to build a barrier to illegal immigrants along the US-Mexico border – has cost $2.4bn so far. Around 960km of fence has been erected, but the remaining 2,090km (1,300 miles) are still to be built, at an estimated cost of $7bn. Between Texas and Mexico the fence hardly exists. The Rio Grande river forms a natural barrier between the two countries all the way along the border.

But the river that Spanish explorers once described as being wider than a shot from a musket has lost much of its strength. The World Wildlife Fund has declared the Rio Grande one of the top 10 most at-risk rivers in the world and depleted water levels are causing unusual headaches for the US border patrol. Mexicans illegally trying to make it to Texas have traditionally swum across the Rio Grande, earning the disparaging name "wetbacks". Now, at Boca Chica, when water levels are low, people can walk across.

There are few other cases where the inequities of the expanding global economy are more glaring than in the US-Mexico relationship. Despite tremendous economic growth in the past quarter of a century, roughly 40% of Mexico's population continues to live in poverty. Current human migration patterns through Mexico's vast territory remain unparalleled in the western hemisphere.

With the proper credentials, thousands of Mexican day-workers are permitted to make the 10-minute journey across official border crossings into the United States every day. Then there are the undocumented poor, without the required permits, for whom the border between the two countries can represent a chance for a better life in the US. Mexican cartels control the border routes, offering guides ("coyotes") but demanding high fees to help people make it across. Stories of betrayal, abandonment and even kidnap by the coyotes are common. Once across the border, the forbidding wastelands can be just as dangerous: in Arizona, the Rio Grande river gives way to the Sonora Desert, one of the most isolated regions in North America. Yet it is littered with debris left behind by thousands of migrants who attempt to sneak in every day.

The US-Mexico border is also a lucrative drugs route, where Mexican drug cartels battle bloodily to control these corridors. Illegal migrants without money to pay for their passage across the border can be used as "mules", carrying heavy 20kg burlap backpacks containing compacted bales of marijuana for as far as 80 miles.

In July, Arizona passed an anti-immigration law that made the failure to carry immigration documents a crime, and gave police the power to arrest on sight anyone suspected of being an illegal immigrant. The Hispanic community – and others – protest that the law is draconian, and will lead to racial discrimination and ethnic profiling; the Obama administration is challenging it, in court, as unconstitutional. Deputy Sheriff Ashton A Shewey, of Arizona's Pinal County police department, is matter-of-fact about what it means to him.

"Half of my daily contacts are with illegal immigrants or Mexican nationals. But we don't 'racial profile' – we only stop people who are breaking the law," he says. "With the new law [SB10-70] we can arrest people who have no ID or won't offer their name. We can detain them while we check them out. Before we would have to call Border Patrol."

Shewey covers an 80-mile area, working in temperatures of more than 37C. He describes the incomplete border fence as a "running joke". The recent shooting of one of Pinal County's deputy sheriffs by a suspected cross-border drug trafficker has further inflamed the situation. "The shooting happened in the foothills of Antelope Peak," Shewey tells me. "One of our deputies apparently stumbled across a group of drug mules, and a gunman opened fire without warning. We had 100 deputies out that night, instead of the usual three. We swept the area and picked up 120 illegals."

While this kind of incident is unusual, a US Border Patrol agent was shot and killed last year close to the Mexican border in Campo, California, and an Arizona rancher called Robert Krentz was also killed on his land near the border earlier this year. These incidents inflame an already heated debate regarding what should be done about illegal cross- border immigration.

Rosie Huey has been a US Border Patrol agent for 10 years in the Rio Grande sector. Like so many of the US Border Patrol agents I met, she is Hispanic. "My mother was born in Mexico, my father in the USA. But he is also of Mexican descent," she tells me, aware of the irony. Many of the illegal immigrants are poor, hardworking people looking for a better life. "It's really hard when we apprehend children and elderly people. Of course we feel compassion. Mexican nationals call us hypocrites and say, 'How can you do this to us?' But I'm doing a job I signed up to do."

The "Minutemen" operating on the US-Mexico border have less sympathy. Some call them "vigilantes", others "patriots": they are armed, civilian volunteer activists who patrol the border in their spare time, reporting illegal immigrants to the Border Patrol.

Al Garza runs one such group, which he calls the Patriot's Coalition. "We've been ripped off and we're being invaded. It's an outright undeclared war against United States sovereignty," Garza says of the vast numbers who make it across the US border illegally. "We need to secure the borders, it's real simple."

Garza tells me he was in the Marine Corps, and fought in Vietnam. "I'm a patriot. My country means a lot to me," he says, sitting in a service station café. "This idiot, Obama, I don't consider him my president. Obama is not an American, and his loyalty is not to the United States. Why should I believe in him? He is a usurper. Well, I've got news for him, he's not going to be president much longer!"

The anger unleashed against President Obama's policies has been startlingly bitter. In April this year at the Southern Republican Leadership conference, Sarah Palin repeated her slogan: "Don't retreat, reload." She insisted it was "not a call for violence", but the very fact she had to explain this part of her rhetoric indicates how extreme the debate has become.

Last year a Homeland Security report on right-wing extremism concluded: "The economic downturn and the election of the first African-American president present unique drivers for right-wing radicalisation and recruitment." In March, a conservative blogger, Solomon Forell, was investigated by the secret service after he tweeted: "We'll surely get over a bullet 2 Barack Obama's head!" and "The Next American with a Clear Shot should drop Obama like a bad habit. 4get Blacks or his claim to be Black. Turn on Barack Obama."

Two years into the rule of America's first black president, the mood along the Rio Grande is turning ugly.