A security guard pushes back a man after he dumped a milkshake on Nigel Farage.Scott Heppell / Reuters

When the Brexit Party leader Nigel Farage was doused Monday with a milkshake while campaigning for the European Parliament elections in the English city of Newcastle, it was unclear whom he was angrier with—the protester who threw the drink at him or the security team that didn’t see it coming.

“It’s a complete failure,” Farage told his security detail as the banana-and-salted-caramel concoction dripped from his lapel. “You could have spotted that a mile away.”

After all, this wasn’t a random attack. “Milkshaking,” as it has come to be known, has emerged as the latest form of protest in Britain, where a number of mostly right-wing political candidates have been drenched by shake-wielding demonstrators on the campaign trail. It began earlier this month when a viral video showed a 23-year-old man throwing a strawberry milkshake on Tommy Robinson, the anti-Muslim activist running as an independent candidate to represent the North West region of England in the European Parliament elections. It was the second time in two days that Robinson, whose real name is Stephen Christopher Yaxley-Lennon, was hit with a milkshake.

Other milkshakings have followed. Carl Benjamin, a U.K. Independence Party candidate for England’s South West region who is currently under police investigation for comments he made about raping British Labour lawmaker Jess Phillips, has faced at least four milkshakings in the past week. Beyond the European Parliament elections, a Social Democratic Party candidate for the British parliamentary by-election in the eastern English city of Peterborough said a protester had emptied a milkshake over a campaign stall.

The deed has become so prevalent that police have even tried preventing people from buying milkshakes near political rallies. Some places, like this McDonald’s in Edinburgh, honored a request by police not to sell ice cream or milkshakes because of their proximity to a Brexit Party rally. Others were less willing.

Milkshakes haven’t always been the obvious choice for political protesters trying to make a statement. While people in other countries have opted to pelt politicians with noodles or yogurt, in Britain the traditional projectile of protest is the egg. Even the most senior of British politicians, from former Prime Minister David Cameron to the former Labour Party leader Ed Miliband, have been hit with eggs. The reason for the egg’s popularity is simple: It is light, compact, and, apart from the occasional rotten one, a seemingly innocuous tool of protest. But eggs are also effective. After all, “nothing strips a politician of his gravitas quite like a slick of yolk drooling down his lapels or shards of shell peppering his side parting,” the freelance journalist Chitra Ramaswamy wrote of Britain’s egging phenomenon for The Guardian in 2015. In many ways, milkshakes are no different.

In other places, though, eggs are still the protester’s edible projectile of choice. In Australia, a 17-year-old was declared “Egg Boy” after he cracked an egg on the far-right politician Fraser Anning for comments in which the senator appeared to blame Muslim immigration for the deadly mass shootings at two mosques in Christchuch, New Zealand.

In Britain, the debate over whether it’s okay to throw milkshakes at politicians has been a somewhat subdued one: While some have noted the time-honored place that nonviolent ridicule of politicians has had in the country, others have argued against throwing things at politicians at all, no matter how minor the object.

Milkshaking may be seemingly harmless, but that doesn’t make it legal. Many of those who have engaged in what has been dubbed “lactose against intolerance” have been taken into police custody. A police spokesperson said the man who threw the £5.25 ($6.68) milkshake at Farage was arrested on suspicion of common assault. If found guilty, the individual, later identified as Paul Crowther, 32, could be fined or face a six-month prison sentence. Still, Crowther said he doesn’t regret what he did with the milkshake, though he added, “I was quite looking forward to [drinking] it.”

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