Rich Barnes says that opposing Israel’s war in Gaza is not a complicated issue.

“Are we for mass murdering babies, or are we against it? To me, it’s a pretty simple equation,” he said, holding Palestinian and Irish flags near the Democratic National Convention (DNC) in Chicago on Monday.

Barnes was one of thousands of protesters who blanketed the grass of Union Park, blocks away from the Democratic National Convention, to demand an end to United States support for Israel’s war.

As the Democrats gathered at the convention to present Vice President Kamala Harris as their presidential nominee, several Palestinian rights advocates told Al Jazeera that they will not vote for Harris unless she agrees to an arms embargo against Israel.

The demonstration, dubbed the “March on the DNC”, also demanded an immediate and permanent ceasefire in Gaza.

“I’m worried because I feel like there’s not going to be any big, major change with her,” Barnes said. “We’re trying to put as much pressure on from the left to say: ‘Listen, you can’t expect our vote.”

The protesters held signs linking Harris and President Joe Biden to the atrocities in Gaza, which they describe as a genocide: an effort to destroy the Palestinian people through bombing and starvation.

“Both Democrats & Republicans have blood on their hands,” one poster read. Another one said: “No votes 4 Kamala until arms embargo 4 Israel.”