For a place with as much common history and culture as Latin America, it is striking how its political landscape is marred by tensions on virtually every border.
A few are serious, but many are downright odd. Chile and Peru quarrel over a grape-based liquor called pisco. A soccer match cased a brief war between El Salvador and Honduras. Bolivia's landlocked navy – seriously – continues to inflame relations with Chile.
The latest conflict erupted before Christmas.
Peruvian President Alan García branded neighbouring Chile a "republiqueta" – a "semi-republic" – because of evidence that Chilean authorities had been spying on Peru.
Just why Chile would want to spy on Peru, García neglected to say.
Former Chilean president Michelle Bachelet denounced García as "offensive and arrogant."
The two countries have long had issues, including the long-fermenting dispute over pisco, which each side claims as its national drink.
"In the case of pisco, the Peruvians do take it pretty seriously," says Albert Berry, an economics professor at the University of Toronto and an expert on South America.
Chile also squabbles with neighbouring Bolivia. The enmity dates to the War of the Pacific, fought from 1879 to 1884, when Bolivia lost its territorial access to the sea.
More than a century later, and still without a seacoast to call its own, Bolivia stubbornly maintains a navy that keeps a few small boats chugging back and forth across the Bolivian half of Lake Titicaca.
"It's a festering sore when you lose territory," says Berry.
Three Chilean architects recently proposed building a 150-kilometre tunnel from Bolivia, under Peru, to a new artificial island to give Bolivia access to the Pacific.
A Bolivian senator criticized the plan as "a mockery and insult to the intelligence of the Bolivian people."
Rarely was a country more miserably served by an aggressive response to Latin America border conflicts than poor Paraguay. It has never fully recovered from a disastrous military adventure that began in 1864 and ended in 1870, when the country single-handedly took on the combined armed forces of Argentina, Brazil and Uruguay in the War of the Triple Alliance.
In that woefully misguided conflict, Paraguay lost more than 50 per cent of its population, either to combat or to disease, and sacrificed much of its territory.
"It was, of course, lunacy," says Berry. In 1978, Chile and Argentina very nearly went to war over three sparsely inhabited islets bobbing in the Beagle Channel – Picton, Lennox and Nueva. The two countries continued to eye each other warily, and traded warning shots more than once, until the dispute was settled under Vatican mediation in 1984.
Colombia and Venezuela are now joined in a state of acrimony that likely constitutes the single twitchiest conflict in the region, the one most likely to escalate into something lethal.
"This is a conflict about ideologies, security and drugs," says Mauricio Cárdenas, former Colombian minister of economic development and now a senior fellow at the Brookings Institution in Washington. "The issues at stake are really very serious."
Venezuela is led by Hugo Chavez, the bumptious left-wing populist and gadfly who loves to get under Washington's geopolitical skin.
The president of neighbouring Colombia is Álvaro Uribe, a faithful Washington ally and the continent's pre-eminent neo-liberal.
Uribe was outraged at evidence, obtained in Ecuador, that Ecuador and Venezuela were supporting Marxist rebels in Colombia. Ecuadorian President Rafael Correa broke off diplomatic ties with Colombia, and Chavez sent troops toward the Venezuela-Colombia border.
War was averted, but tempers remain brittle.
Experts say armed hostilities between the two countries are unlikely, but that's merely the logical view.
"Wars aren't the outcome of logical factors," notes Cárdenas. "Who knows what's going on in Chavez's mind?"
The likelihood of having war in South America is small," says Ronald Rojas, a Bolivian who manages a program on Latin American health and education at the Ottawa-based Canadian Foundation for the Americas.
"But issues might arise. These types of bilateral relations are really emotional, and at some point two presidents are going to remain emotional."
A shot of pisco, anyone?