What are the three levels of structural dependency of interrelationship? Why did these theories fail?

The structural dependency perspective focuses on the inter-relationship at three levels - the international economy, the nation-state, and the alliance of social classes within the state, Such theories failed to have a long life. They became unfashionable in the 1980s for the main reason that their empirical base was very weak. it appeared that the sociopolitical consequences of underdevelopment and dependency had been worked out without much precision and evidence.