Cuba - Exploiting the US-Soviet Cold War, he was for decades able to rely on strong Soviet backing, including annual subsidies worth $4-5 billion, and succeed in building reputable health and education systems. But, at least partly because of the US trade sanctions, he failed to diversify the economy. The disappearance of Soviet aid following the collapse of the USSR forced the government to introduce tight rationing of energy, food and consumer goods. The economy has soldiered on with the help of Canadian, European and Latin American investments, especially in tourism. Controls were relaxed in the 1990s, with companies allowed to import and export without seeking permission and a number of free trade zones opening up.