The concentration of all political authority in the central bodies of the party has effectively precluded the emergence of any open opposition to the PCR leadership as well as the assertion of any particular group interests. Under Ceausescu's leadership the party has sought to strengthen its role in all spheres of social, economic, and political life and, at the same time, to broaden its base of support by taking steps to increase its membership. Although the party leaders have periodically demonstrated a cautious relaxation of the highly centralized system of control, the PCR has continued to be extremely sensitive to any potential threats or challenges to its position. In attempting to build a broad base of popular support the party has drawn upon the symbols of nationalism and has made extensive use of Romanian history and tradition. Its independent stance in relation to Soviet domination has served to enhance its image among the general population; at the same time, the fact that membership in the party has been made relatively easy has helped the PCR become one of the largest communist parties of Eastern Europe. In mid-1971 Ceausescu initiated a campaign to strengthen ideological and cultural orthodoxy and, for the first time in the six years since he had come to power, some political observers believed they were able to detect opposition to his proposals both within and outside the party. There was no indication, however, that the resistance was organized or was strong enough to affect Ceausescu's position. Throughout the period of Ceausescu's control there have never been any recognizable factions in the party in opposition to his leadership. MAJOR POLITICAL DEVELOPMENTS, 1965 TO 1970 The leadership of the PCR changed hands in March 1965 when Nicolae Ceausescu became first secretary after the death of Gheorghe Gheorghiu-Dej, who had headed the party almost continually since 1944 (see ch. 2). Ceausescu's emergence as head of the party came in the midst of a period of growing Romanian nationalism that had begun in the early 1960s. Initiated by Gheorghiu-Dej, the policy of greater national autonomy was given additional form and substance by Ceausescu, who sought to cast himself in the role of the restorer of Romanian history and the country's national traditions. As Gheorghiu-Dej's successor, Ceausescu was confronted with the necessity of consolidating his power. No member of the party Secretariat owed his position to Ceausescu, and he found particular challenges to his authority from three men who had been among Gheorghiu-Dej's closest associates: Chivu Stoica, a veteran party leader; Gheorghe Apostol, first deputy premier and a former PCR secretary; and Alexandru Draghici, minister of internal affairs and, as such, head of the powerful state security apparatus.