As the Sinn Féin leadership under Gerry Adams and Martin McGuinness turned toward a peace process strategy, Donaldson was dispatched to New York City, where he helped establish Friends of Sinn Féin, an organisation that solicited mainstream political and financial support for the new strategy while attempting to isolate hard-line activists in Irish Northern Aid and other support organisations in the United States. Martin Galvin, a Bronx-based Irish-American attorney and future dissident republican, later claimed that he had warned the republican movement's leadership that he suspected Donaldson of being a British government informer.