While expanding economic activities, consumer demand and accelerating population settlement were the principal forces fuelling Bangkok's growth, state agencies did play a significant role in setting a framework(intended and unintended) conducive to change and urban growth. The development programmes set in place from the First National Development Plan directed government expenditures and development and principally towards energy and transport infrastructure(Pasuk 1980: 64). They had the cumulative effect of reinforcing the capital's economic dominance, exacerbating regional inequalities and accelerating the transition towards a road-based city. Under the impetus of US advice, aid and loan funding, highway construction received considerable attention. Many provincial road projects were aimed primarily at enhancing military security in the northeast(towards the Lao border) but they had a catalysing effect on trade and transport flows(Muscat 1990: 313; Porphant 1994: 289). Major highways built in the late 1950s such as Sukhumvit(linking Bangkok to the Cambodian border) and the Friendship Highway(connecting the capital to Nong Khai in the northeast) had the almost immediate effect of stimulating road traffic(Muscat 1994: 120; Porphant 1994: 300-1). The new highways and associated secondary road network not only stimulated economic activity(which was an explicit NEDB objective) but also facilitated the movement of people to the capital, particularly from the impoverished north-east, a distinctive regional flow which accelerated from this time.