US Republican congressman and senate candidate Todd Akin caused a storm last week with his comments about rape. In case you missed the excruciating moment, here it is again:

'Legitimate' rape?!

Akin, it seems, was keen to point out the distinction between different kinds of rape: the "legitimate" rapes, and the other, "consensual" kind.

This prompted Salon.com to create a helpful guide to "legitimate rape," which asks readers: "Have you recently sexually violated someone and are now asking yourself, 'Hey, does that count?' Confused about the differences between date rape, acquaintance rape, marital rape and real rape that actually matters? We’re here to help."

Naturally, Twitter was soon abuzz with put-downs in a similar vein, with one tweeter describing Akin as "more out of date than an 1823 textbook. Literally," while another asked, "Is it possible to win a Senate race with 0% of the women's vote? Asking for a friend."

The fun continued: "Magic sperm-rejecting vaginas is the name of my band," declared one, and another: "Tomorrow, Todd Akin explains that legitimate murders don't cause death." Oh, and of course: "You can't gain weight if you eat legitimate food."

Laughing aside...

The whole business might have been a lot more fun, however, had Akin's remarks not sounded so familiar. Exhibit one: Republican vice-presidential candidate Paul Ryan's notion of "forcible rape", created to restrict rape victims' access to abortion. Exhibit two: British justice minister Ken Clarke's claim that there's a difference between rape and "serious rape".

But famous British MP and foot-in-mouth regular George Galloway won the outrage competition by declaring that, in reference to the Julian Assange allegations, having sex with a woman when she is asleep is not rape, just poor sexual etiquette. "I mean, not everybody needs to be asked prior to each insertion," he added gallantly.

It might have been more fun, too, if every one of the above opinions had not been aired by powerful men during the last two years. We've come no further, it seems, than 1990, when failed Republican gubernatorial candidate Clayton Williams Jr compared rape to bad weather, saying, "If it's inevitable, you might as well lie back and enjoy it".

So, when is rape rape?

Did we really need the president of the United States to remind us that "rape is rape"?

Rape happens to men and women, children, husbands, wives, boyfriends, girlfriends. It happens in prisons and in the bedrooms of people who invited the rapists in. It's a crime rooted in violence and domination; a crime that clearly isn't understood by many of the politicians who try to fit it into rigid definitions.