The power of a fast-food chain to clog a nation's arteries and fill its cities with hideous drive-thru stores is not in doubt. But Burger King might have just gone a step too far – by poking fun at the proud nation of Mexico.
In what headline-writers have dubbed "a whopper of an insult", the Florida-based firm has stoked diplomatic tensions between the US and its neighbour by launching a TV ad that plays on a "stereotyped" image of Hispanics.
The commercial, for BK's "Texican" burger, shows a short, squat wrestler in a poncho resembling the Mexican flag. He teams up with an American cowboy, twice his height, to illustrate that the sandwich contains "the taste of Texas with a little spicy Mexican".
It caused outrage for two reasons. Firstly, the ad suggests Mexicans are shorter, uglier, and accustomed to looking up at alpha males from north of their border. Secondly, it contains a disrespectful use of the national flag.
Jorge Zermeno, the Mexican ambassador to Spain, where the ad first aired, wrote a formal complaint to Burger King, asking for the ad to be removed.
"[They] improperly use the stereotyped image of a Mexican," he told Madrid's Radio Formula station this week. "We have to tell these people that in Mexico we have a great deal of respect for our flag."
Mexico has strict rules governing the use of its flag. Last year, it fined the publisher Random House over an ad for one of Paulo Coelho's books that revolved around a man using a flag as a cape.
The controversy was brought to the attention of America's large Hispanic community by the Associated Press yesterday, prompting a rash of reports that can only damage Burger King's standing in the crucial demographic.
It has also come at a bad time for cross-border relations, which are strained because of America's role in buying the drugs and selling the firearms that are fuelling the "drug war" that has killed 7,000 Mexicans in the past year.
Burger King has yet to comment on the ad but it might have been expected to know better: in the 1990s, the rival fast-food firm Taco Bell caused a huge row by airing a commercial that featured a tiny talking Chihuahua who spoke with a Mexican accent.