21 set 2015 ano - US as a superpower in the 21st century

Descrição:

The USA has by far the world’s largest and most technologically advanced fl eet of
warplanes, ships, tanks and artillery systems. These give it dominance over air, sea and
land. For example, most US warplanes, bombs and missiles are made by a small group of very
large contractors, including in particular Lockheed Martin, Boeing, Raytheon, TRW and
Textron. In 1998–9, Lockheed Martin employed 130,000 people in the USA and overseas
and had over 900 facilities in 45 US states

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