Mining economy. – The gradual depletion of many deposits subject to periods of intense exploitation and the need not to affect the reserves in a decisive way have limited the expansion of a large part of mining production. If the levels of internal supplies remain rather constant, this is mainly due to the continuous technological updates in the field of research and cultivation of the fields. The USA, however, tends to become more and more an importing country of minerals; their industrial system requires increasingly large supplies from other parts of the world: the situation is deficient especially for zinc, nickel, manganese, antimony, lead, copper, mercury and many other strategic raw materials for the power supply of a modern industrial apparatus. This has long led the large US companies to ensure control of mineral deposits located outside the borders of the Confederation, especially in Latin America, generating a series of very dense economic interests that have not failed to reflect on the political framework of this part of the Earth.. On the other hand, the USA continues to have a monopoly on the production of molybdenum, vanadium and tungsten, while it has come to extract almost half of the world total of uranium ores coming mainly from New Mexico, Colorado and Utah (see. tab. 6). generating a series of very dense economic interests that have not failed to reflect on the political framework of this part of the Earth. On the other hand, the USA continues to have a monopoly on the production of molybdenum, vanadium and tungsten, while it has come to extract almost half of the world total of uranium ores coming mainly from New Mexico, Colorado and Utah (see. tab. 6). generating a series of very dense economic interests that have not failed to reflect on the political framework of this part of the Earth. On the other hand, the USA continues to have a monopoly on the production of molybdenum, vanadium and tungsten, while it has come to extract almost half of the world total of uranium ores coming mainly from New Mexico, Colorado and Utah (see. tab. 6).
Industrial activities. – The rise of US industry continued at a dizzying pace throughout the second post-war period and only recently did it warn of deceleration beats in relation to the global crisis of the industrial system also linked to the rise in the prices of raw materials. The trend towards industrial concentration was still accentuated and the giants of the sector were increasingly projected abroad, building numerous plants in those areas that offered better market opportunities (such as Canada and Western Europe). The weight of technological research has become essential, linking company, state (especially the Department of Defense) and university laboratories in a series of relationships and in a competitive relationship, which have given multiple fruits for the raising of production levels and for the improvement of old products or the introduction of a wide range of new productions. The USA also continues to benefit greatly from the overseas sale of patents that their efficient research apparatus is churning out at a very rapid pace.
The manufacturing industry as a whole employed just under 20 million people in 1970; but, even in the context of a general expansion of production potential, not all branches showed increases in employment. Some traditional sectors, such as the textile sector of the East, have reported, for example, despite the massive production, a decrease in employees and the dismantling of more obsolete plants. However, the production of artificial textiles (in 1976 over 160,000 t of fiber and 220,000 t of staple) and synthetics (1,734,000 t of fiber and 1,794,000 t of staple in 1978), which have often replaced along the front of the fall line (eastern foothills) the wool and cotton companies.
The main branches remain largely the steel industry (116 million tonnes of steel in 1976) and the mechanical one (in which the automotive industry continues to emerge: about 8 million employees, 9.2 million cars and 3, 5 million commercial vehicles in 1977); they always place the USA first in the world for many of the productions and feed a complex panorama of related activities (think, for example, of the 230 million tires produced in 1977).
There are, however, industrial activities that show a greater rise than the others: such as chemicals (and petrochemicals), which from the traditional districts of the Northeast has been expanding into the Center, particularly in the oil states (the refineries of the USA now exceed 780 million tonnes of processing capacity), with the Baton Rouge and Houston areas at the head; and like the air force, which has been locating itself mainly along the Pacific coast, in Kansas, Missouri, Georgia and Texas (as well as in the old industrial districts of the Great Lakes and the Atlantic coast). The electronic and aerospace industries, in many ways connected, which have allowed the USA to conquer prestigious achievements in the field of
