Anti-Israel activists are clamping an effective blockade on the Jewish state — from inside the U.S.

Thousands of pro-Palestinian protesters successfully blocked an Israeli cargo ship from docking in Oakland, California, Saturday evening, in response to Israel’s military operations in Gaza over the last month, Al Jazeera reported.

Demonstrators wave Palestinian flags and signs as they march to berth 57 at the Port of Oakland in Oakland, Calif., on Saturday, Aug. 16, 2014. (AP Photo/The Tribune, Ray Chavez)

Saturday’s protest drew several thousand people, Al Jazeera reported, one of a slew of “Block the Boat“ events planned for the West Coast, with similar actions slated for Seattle and Tacoma, Washington, on Wednesday and, later, Vancouver.

If all the protests are successful, activists said, Israeli shipping could be effectively locked out of the western U.S. and Canada.

The protests are fueled, in part, by trade unions.

“Palestine is calling us to action!” a leaflet advertising the protest read. “Palestinian laborers [and the] Palestinian General Federation Trade Union have called on workers around the world to refuse to handle Israeli goods.”

The target: Zim Integrated Shipping Services Ltd., Israel’s largest shipping company.

The blockade bears a resemblance to actions taken in 1984, when International Longshoremen and Warehousemen Unions members protested apartheid by refusing to unload South African cargo in San Francisco. While pro-Palestinian activists often draw parallels between apartheid South Africa and the situation in Gaza and the West Bank, the ILWU sat on the sidelines Saturday.

“The ILWU is not involved with any actions regarding incoming Zim ships,” ILWU spokeswoman Jennifer Sargent told Al Jazeera.

Image via Facebook

Image via Facebook

Activists said they’re still counting on support from individual union members.

“We trust that in line with their long legacy of political protests that they will honor our picket and not work the Israeli Zim ship,” said Mohamed Shehk, media and communications officer for Critical Resistance, one of the “Block the Boat” organizers.

He said that if enough protesters show up, dock workers won’t be physically able to unload the Israeli ship.

Demonstrators wave Palestinian flags and signs as they march to berth 57 at the Port of Oakland in Oakland, Calif., on Saturday, Aug. 16, 2014. (AP Photo/The Tribune, Ray Chavez)

“It’s on us to ensure that the action is successful enough that they don’t have to make a choice,” Shehk said.

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