FEW AMERICANS HAVE had the opportunity to see firsthand, as I did in early July, the devastating impact of Israel's occupation of the West Bank and East Jerusalem, and why it's critical that we support President Barack Obama's call for a settlement freeze.

Settlements are the capstone in a system that gives Jewish people like me privileges and rights at the expense of the indigenous Palestinian population. Settlements, and the infrastructure of population separation, land appropriation, lawless violence and ethnic discrimination that supports them, are at the core of the conflict between Israelis and Palestinians.

Settlement expansion is made possible by some $3 billion in military aid the U.S. gives to Israel each year, and additional millions in subsidies provided by U.S.-based Jewish and fundamentalist Christian nonprofits.

That is why Obama has called first for the freeze of settlement expansion, to be followed, presumably, by negotiations to dismantle them and either swap or return this conquered and stolen land.

What exactly are these settlements, where nearly 500,000 Jewish people now live?

They are communities created on land taken by force in 1967 and held and developed only through the extensive use of military power. Served by Israeli state-provided electricity, water, sewage and road construction, settlements are illegal under international law (the 4th Geneva Conventions prohibits an occupying power from transferring its population onto occupied lands).

Some 40 percent of the land on which settlements sit is known to be privately-owned Palestinian land. Israel continues to confiscate more land — including the water aquifers and arable farmland on which the Palestinian economy relies — for the Separation Barrier (or Wall), new houses, and to build a network of bypass roads on which Palestinian cars are banned.

In U.S. and internationally-brokered agreements, Israel has already agreed to end settlement construction. Yet, during the last six years, the settler population in the West Bank (not including East Jerusalem) actually rose 37 percent. Forty percent of the increase in the settler population came from immigration, both from abroad and inside of Israel, incentivized through subsidies and discounts.

That's not natural growth, the excuse the Israeli government is using as a cover for continued settlement growth.

Meanwhile, Israeli soldiers mainly do nothing while settlers attack Palestinian farmers and their families. Settlers threaten Palestinian lives and especially livelihoods in numerous ways, such as by obstructing harvests and cutting down groves of olive trees, burning agricultural fields and intimidating people from their land so that settlers can claim it. The Israeli human rights organization Yesh Din says these Jewish groups perpetrate "systematic, organized and large-scale terrorist actions." The perpetrators are rarely brought to justice: 90 percent of complaints are closed by the police.

We need Obama and his foreign policy team to immediately hold Israel accountable for the welfare of the Palestinians living under Israeli occupation, which means an end to all settler violence, an end to the expropriation of Palestinian land, and an end to the destruction of Palestinian homes, including in East Jerusalem.

Obama should pressure Israel to end financial and other incentives that encourage Jews to move to the West Bank. Congress should support Obama in taking these steps because they are the right thing to do and because they are the only path toward resolution and an end to the conflict.