"Unlike in World War II, the enemy this time is within," says Robert Russell, an artist from Los Angeles.

Last week, a series of posters designed by Russell appeared pasted onto walls and lampposts on the streets of the US capital.

From a distance, they look just like American propaganda posters from the Second World War. But a closer look reveals that it's not Adolf Hitler "caught with his panzers down," as in the original 1930s poster, but a trouser-less President Donald Trump, wearing boxer shorts adorned with red Swastikas. Underneath are the words: "His true colors are on display."

In the original, Hitler was 'caught with his panzers down'

"I'm not saying he's Adolf Hitler," Russell explains. "But Trump is certainly flirting with Nazis and allowing that base of his support to march around in Charlottesville carrying Swastikas."

Read more: White supremacy and neo-Nazis in the US - what you need to know

Russell is referring to a white supremacist rally that took place in Charlottesville, Virginia, in August. Right-wing protesters clashed with counter-demonstrators on the streets of the university town. A 32-year-old woman was killed and 19 people injured when a car, allegedly driven by a Unite the Right rally-goer, sped into pedestrians.

President Trump condemned the violence "on many sides," but he was criticized for failing to speak out specifically against the white supremacist and neo-Nazi groups present.

Russell, for one, was not satisfied with this response. "In the 1930s in Germany these sorts of flirtations led to what we all know happened," he says.

Read more: Three things that make the violence by the extreme right in Charlottesville unique

The right side of history

Russell's posters appeared in Washington, DC just in time for politicians' return from summer recess. According to Arianna Jones, who came up with the initial idea for the poster campaign, the images are intended to encourage US lawmakers to "get on the right side of history."

"Extremism is only made possible by its normalization," Jones says. "If a 20-year-old woman under the threat of guillotine can speak out for what is right, it's the least we can ask of a bunch of old white guys and their staffers safely ensconced in their Capitol Hill townhouses."

Hans and Sophie Scholl

The young woman Jones refers to is Sophie Scholl – a former Hitler Youth member who would become one of Germany's most celebrated anti-Nazi heroes. In her honor, Jones and Russell have entitled their collection of political posters "The Sophie Scholl Project.”

Scholl and her older brother Hans were members of the White Rose pacifist resistance group, which produced and distributed anti-Nazi leaflets. "We will not be silent," read one leaflet. "We are your bad conscience. The White Rose will not leave you in peace!"

On February 18, 1943, the Scholl siblings tossed hundreds of the pamphlets into the atrium of the University of Munich. It was a daring act of public protest, and it cost them their lives; they were executed soon after at the hands of the German secret police.

Read more:

Sophie, Hans Scholl remain symbols of resistance

Speaking truth to power

For Germans today, Sophie Scholl is a positive symbol from a dark time in the nation's history. Every German school child knows her name. Streets, parks and buildings across the country are named after White Rose activists. But what about across the Atlantic?

"Now and again different progressive protest organizations in the US have picked up on the White Rose, and especially Sophie Scholl, as a symbol to mobilize people to act," says Dr Jud Newborn, historian and co-author of "Sophie Scholl and the White Rose."

Read more: Scholls were 'a sign that resistance was possible'

Many of the posters were ripped down after a few days

"However, it's only in the last few years – especially since the election of Donald Trump and his sadly right-wing agendas – that Sophie has suddenly sprung into the American consciousness," he adds.

Newborn believes that Trump's perceived encouragement of so-called "Alt-Right" groups has awakened a sense of urgency among the progressive Left. He sees the White Rose as a "natural" source of inspiration for the latter.

"Under conditions far, far more grave than anything going on in the US today," he explains, "the White Rose did something that is nonetheless essential everywhere, if one is brave enough: to speak truth to power - and early enough so as to try and nip any dangerous developments in the bud, before it's too late."

Read more: Germany, Israel repulsed by Nazi-style salutes at pro-Trump event

A slur on President Trump?

While the Holocaust scholar advises against drawing "sloppy comparisons" between Nazi Germany and the present day, he has no qualms with Russell's posters.

A reference to Trump's venomous use of Twitter: not all the posters use Nazi symbols

"The artist is using slightly provocative and mostly entertaining art to rightly draw attention to the dangers we currently face in the US," Newborn says. "Not so different from the act of political theater that Sophie and Hans Scholl staged in Germany."

But not everyone agrees. Rabbi Marvin Hier, who spoke at President Trump's inauguration, calls the art project "outrageous."

"Trump has made mistakes, in my opinion," he says. "But to equate him to being a Nazi is over the line, preposterous and untrue."

Read more: Historian: Comparing Trump to Hitler is a distraction

"We live in a free country. You can criticize presidents, you can criticize everybody – that's what's great about America!" Rabbi Hier continues. "But to accuse any President of the United States using the symbols of the Nazis does not gain my sympathy. The Swastika to the Jews equals the crematoria."

For Russell, who is himself Jewish, this opportunity to reappropriate Nazi symbolism is part of his posters' appeal. He feels this is a time for him to "set down the paintbrushes and pencils" from his day-to-day art work and do something more "direct" – and he finds inspiration in historical characters like Sophie Scholl.

"Because I'd like to think that, were I alive at the time, I would not have just passively endured my fate," he says. "I'd like to think I would have fought back in some way."