Throughout the Vietnam War period, Korean troop presence in Vietnam played a key role as leverage to obtain every possible economic and military gain from the U.S. Every international issue surrounding Korea was related to the Vietnam War by the Korean government and positively contributed to the increase of Korea`s voice at the negotiation table with the U.S. The Vietnam War affected the entire Korean society in so many ways that everyone`s life was touched at some point if only by the atmosphere it created. For some, the war presented an opportunity for private gains regardless of morality or justification; no qualms intruded upon their actions, and no nagging doubts restrained them. The most significant result of Korea`s engagement in Vietnam was to be found in the economic arena, and other changes in the domestic and international posture of the Park`s administration were largely a corollary of the economic situation. Korea was able to accomplish most of what the new leaders had expected from the war largely due to the U.S. honoring of promises of economic support, which resulted from the Vietnam negotiations, although many security concessions including the military modernization of the Korean forces were not completed on schedule or were postponed until other security issues providing leverage for Korea occurred. In 1970 Senator James Fullbright commented during the "Symington Hearings" on the U.S. security situation overseas that Korea`s involvement in Vietnam hardly seemed such a heroic gesture. Having been informed of Korea`s massive earnings sanctioned by the Brown Memorandum, Fullbright was of the opinion that Korea had been prompted more by profit motives than a sense of self-sacrifice. In fact, Korea had received covert U.S. funding and military assistance in exchange for its military participation in Vietnam. By 1966 Korea`s financial position as provider of troops had strengthened considerably and the Brown Memorandum of March 4 established the arrangement by which America would use Korean troops for the duration of the war. The Koreans had insisted upon the memorandum as a formal guarantee of American payment and assistance for Korean forces. Payments were channelled to the Korean in many different ways, notably through the U.S. AID and by facilitating war profiteering by Korean businessmen. The Korean economic miracle was founded upon its exports and subsidies in excess of $1 billion. Not only did the government benefit but also businesses, contractors, soldiers and a lot of shady operators. In addition to these benefits, largely helped by Vietnam-related public and commercial loans from the U.S., Korea was able to pave the way for the expansion of its industrial infrastructure and promote to develop target and strategic industries such as heavy and chemical industries, which became a core factor of Korea`s economic growth since the end of the Vietnam War. These strategic industries were led by "Vietnam-born" chaebol groups such as Daewoo, Hyundai, and Hanjin because the Korean leadership granted them favours in return for their remarkable achievement in Vietnam during the war period. However, the Korean government`s forcible measure of export promotion to Vietnam with the commodities which Korea did not have the capacity to produce led to the reexport of Japanese semi-finished goods and culminated in the structural dependence of Korea upon imports from Japan in the coming decades and a large trade deficit.