社会主导型:由于美国的公益意识比较成熟,所以公益广告的发展是由社会各方共同推动的。美国是现代意义上公益广告的发源地。1942年太平洋战争爆发后,美国的企业建立了战时广告理事会。仅仅是动员战时债 Social-led: As the public awareness of the United States is relatively mature, the development of public service ads is promoted by all sectors of society. The United States is the birthplace of public service announcements in the modern sense. After the outbreak of the Pacific War in 1942, U.S. companies established the Wartime Advertising Council. Just to mobilize wartime debt