The sun was shining and the streets of Milwaukee, on the frigid shores of Lake Michigan, were full of demonstrators. More than 150 businesses shut their doors on Monday as part of the #DayWithoutLatinos. The Wisconsin non-profit Voces de la Frontera organized the protest together with Muslim and anti-racist organizations. Undocumented immigrants play an enormous role in Wisconsin’s economy, especially in the state’s dairy industry.

In Milwaukee, tens of thousands on strike and marching, hundreds of businesses closed to #StopClarke #daywithoutlatinos pic.twitter.com/YmUJ0wr3aS — Voces de la Frontera (@voces_milwaukee) February 13, 2017

The protesters had left workplaces, schools and farms. School students were excused from class if they had their parents’ permission. Busses had arrived from more than 25 cities across the state. They gathered at 11am and marched through the city center to the Milwaukee County Courthouse. They chanted: “Si se puede!” and “El pueblo unido jamás será vencido!”

“We are workers, not criminals” read one banner at the front of the march. While some U.S. labour unions have fallen for Trump’s chauvinist logic of protecting jobs by keeping out so-called “illegal aliens”, other unions recognize the need for the unity of all workers, with or without documents. The Milwaukee Teachers’ Education Association was one of several trade unions supporting the protest.

#StopClarke was a central slogan. Milwaukee Sheriff David Clarke wants to enroll his department in the 287(g) program of the Immigration and Custom’s Enforcement (ICE). This would allow his officers to act on behalf of ICE, giving them the power to arrest and detain undocumented people. In a Facebook post, Clarke justified a crackdown with racist hogwash, including the need to “prevent the spread of infectious diseases e.g. H1N1 flu, ebola”, as well as stopping refugees who “would overwhelm America’s limited public services”. The sheriff called for “zero tolerance”.

Clarke, who has been pictured with his absurdly oversized cowboy hat at Trump Tower, is one of approximately three black people who support the US president. He got national attention for a breathtakingly racist speech at the Republican National Convention, specifically attacking the Black Lives Matter movement as a “hate group” who “will join forces with ISIS”.

Interestingly, even the Milwaukee police have come out against the sheriff, as well as the county supervisors. Trump’s plan for increased deportations – even more than the 2.4 million people deported during Obama’s two terms – is dividing the US state apparatus at all levels. The problem is that the US economy is dependent upon the labor of undocumented workers. Even the most racist policies are designed not to deport all immigrant workers, but rather to make them live in constant fear and accept greater rates of exploitation.

I wouldn't say the Day Without Latinos crowd was "yuge" but I would say it was HUGE. #diasinlatinos @voces_milwaukeehttps://t.co/3URSYTwQGL pic.twitter.com/GD3ypmTmPN — Jimmy Carlton (@jimmycarlton88) February 13, 2017

The Milwaukee protest shows part of the way forward for the resistance against Trump: Workers withdrawing their labour power and collectively shutting down the economy. The left and the workers’ movement – including all the immigrant workers – needs to urgently discuss how we can advance towards a general strike across the country.