For much of the twentieth century, Congress and the president were rivals for determining the organization of the executive branch. The events of September 11, 2001 did not end that contest. The president sought to be the architect of new arrangements for protecting and maintaining homeland security, a nebulous term seeking to be a policy concept. Initial institutions created to exert leadership and coordination on behalf of the president were the Office of Homeland Security and the Homeland Security Council, simultaneously established by an executive order. Several months later, the president called for a new administrative organization, and steadfastly pursued the mandating of a Department of Homeland Security, composed of existing entities of his choosing and vested with managerial flexibilities he considered to be essential. Ultimately, he largely obtained what he wanted in the legislation mandating the department.