Israeli Prime Minister Benjamin Netanyahu of Israel made a direct appeal on Tuesday to Democrats still troubled by the public feud over the nuclear deal with Iran, appearing at a leading liberal think tank aligned with President Obama to declare that support for his country in the United States must remain a bipartisan proposition.

At an hour-long appearance before the group, the Center for American Progress, Mr. Netanyahu fielded questions and defended his policies in front of an audience of leading foreign policy experts, Democratic operatives and Jewish activists, projecting a benevolent tone even as he countered criticism of his approach to resolving the conflict between Israelis and Palestinians.