and it was another male judge, William O. Douglas, who replaced Justice Brandeis. For the next few years, every time a vacancy occurred, Allen's supporters would again suggest her, but to no avail. Continued advocacy On the Circuit Court, Sixth Circuit, she heard cases from Ohio, Michigan, Kentucky, and Tennessee. In 1940, she wrote This Constitution of Ours. Even after World War II broke out, Allen remained steadfast in her determination to work for peace. She continued speaking and gave talks both in person and on radio. In 1944, the National Association of Women lawyers put her name forth as someone who should be involved in international peace negotiations. When the war ended, she continued to speak to civic groups, especially women's clubs. Her message was that relying on the United Nations would not prevent the next war. It was essential for individual citizens to keep demanding that each country—whether large or small—have respect for the rule of law. "To secure peace, there must be justice," she told 3,000 attendees at a conference of the National Federation of Business and Professional Women's Clubs. "There cannot be justice unless there is a rebirth of moral principle among the nations. There cannot be a rebirth of moral principle unless the conscience of the peoples becomes articulate." Allen herself remained a very articulate spokeswoman on the issues she cared about. She was regarded as such a credible figure that in 1947, the American Academy of Political and Social Science asked her to do a study of women's voting patterns, to offer her assessment of whether women were in fact using the franchise, and whether they were active in the political process. In later talks, Allen expressed the opinion that while many women were in fact voting and speaking out on issues, there was a generational shift taking place. The dynamic women leaders who had fought for suffrage and brought about greater participation for women in other areas of public life were now deceased, and they had not yet been replaced. She expressed concern about this lack of new and dynamic leadership, and hoped new leaders would emerge. Renewed Supreme Court speculation Allen's supporters again sought to have her appointed to the United States Supreme Court during Harry S. Truman's presidency, but Truman seemed to be opposed to having a woman sitting on the highest court of the land. Allen was later told that