Prosecutors accused two Arab-Americans on Thursday of supporting murder and mayhem in Israel by helping funnel money to and coordinate the activities of Hamas, which was elected to power this January but remains designated by the US as a terrorist organisation.
Many in the Arab-American community see the case as part of a broader crackdown on Muslims living in the United States and an erosion of constitutional guarantees of due process and a fair trial.
Bassel Abushaban, a member of the Palestinian-American community, told AFP after watching opening arguments with around 50 other Palestinian-Americans: "It's a case the community feels is just the beginning.
"Everyone is afraid of even thinking about helping their families. The message that is coming out of this is that any organisation that is helping the Palestinian people is going to be shut down."
Muhammad Salah, a grocer from Chicago, spent nearly five years in an Israeli prison in the mid-1990s after admitting he committed a number of crimes on behalf of Hamas.
Prosecutors say those statements prove his fund-raising activities in the US were aimed at violent ends. His defence team argues that they were obtained by torture.
Abdelhaleem Ashqar, a former business professor, was twice jailed in the US for refusing to testify to a grand jury about the activities of Hamas.
His defence team said he is a peaceful activist targeted for refusing to spy for the US government. Prosecutors say he served as a top secretary, redirecting money and information from his Mississippi home and organising high-level strategy meetings.
Carrie Hamilton, a prosecutor in the case, told the jury: "Hamas is not a legitimate political organisation just trying to make a difference.
"Hamas is a sophisticated global terrorist organisation. Although the violence happened in Israel ... the funding and the planning happened right here in the United States by members like Muhammad Salah and defendant Ashqar."
Hamilton said these two men actively coordinated activities with Musa Marzook, a senior Hamas figure also named in the indictment who is considered a fugitive living in Syria.
Defence attorneys noted that the crimes they have been accused of participating in occurred before the US designated Hamas as a terrorist organisation.
Salah's attorney gave jurors a lengthy description of the history of the Israeli-Palestinian conflict and compared Hamas to the French resistance under the Nazis and the African National Congress' struggle against Apartheid in South Africa.
Michael Deutsche told jurors: "Any time you have an occupation there is going to be a resistance. You may disagree with that, but that doesn't make them terrorists."
He said Hamas was far more than a resistance movement. He said it operated schools, day care centres, sports clubs and other social organisations and - unlike the corrupt Palestinian Liberation Organisation - could be counted upon not to skim off the top of charitable donations.
It was these humanitarian activities that Salah supported, Deutsche said.
Ashqar's attorney painted the case as a crackdown on US guarantees of freedom of expression and association.
William Moffitt told the jury:"Dr Ashqar sought to change our ideas about what was right in Palestine and Israel."
"There is nothing illegal about opposition. There is nothing illegal about organising that opposition."
Both men face a maximum of life in prison on racketeering and obstruction of justice charges.