There was a time when spam didn’t denote unwanted email from vendors of products designed to enlarge parts of the anatomy not usually discussed in polite company.

Just as now, I don’t remember spam ever being rationed – I’m not sure why – but I do recall enjoying it fried.
From here:

How the US cemented its worldwide influence with Spam.

[T]he flagship of American influence in my own life was Spam, the bright-pink pork luncheon meat that was a staple of the British working-class diet for several decades.

It’s still going strong in many markets around the world – including the United States – and although the odd concession has been made to changing times (it’s less fatty and salty than it used to be) it’s still essentially the same as it always was.

I came to know it in the early 1960s, in the days before the invention of obesity. In common with millions of other British families we used to slice it, coat it in batter and then deep-fry it, thus producing that miracle of British culinary ingenuity known as the spam fritter.

So when the time came to find a way to round off my three years as the BBC’s North America correspondent, it seemed somehow fitting to head not for the bright lights of New York or Chicago but for the less showy charms of Austin, Minnesota, home of the Hormel Food Company. Spam Central, in short.

It would be fair to say that Austin, like a lot of cities in the northern Mid West, is not flattered by the grim, flat light of early winter. But the Spam Museum, which is its main tourist attraction, is a riot of cheery colour.

Inside you are treated to the services of a “Spambassador” (I said it was colourful, not subtle) and you enjoy a movie presentation that draws heavily on the musical work of a group of ladies called the Spamettes.

And it turns out that it’s not fanciful at all to see Spam as a symbol of the spread of American influence.

Our Spambassador Chris George tells us that the product was already popular in the United States in the 1930s – the first radio jingle, in fact, is a kind of ode to Spam set to the tune of My Bonny Lies Over the Ocean.

This, of course, is the definitive ode to spam: