Liberal theorists argued, prior to World War I, that war seemed obsolete in part because countries could not afford it. Their arguments against war did not stop there, however. Some of their other arguments even won popularity again in the 1970s. What did these include

B. ideas about using smarter diplomatic means of shifting regional balances of power

Explanation:

Options are the following:

A. the idea that changes in the balance of power were never a true cause of conflict between states

B. ideas about using smarter diplomatic means of shifting regional balances of power

C. the idea that international institutions would come to dominate world politics over time

D. arguments involving the increasing economic interdependence of states, and the increasing of transnational social and political ties

After the world war I, people realized that war needs more resources and money which can't afford by the countries that are involved in this war. This war destroy the economic condition of different countries. So they want to end the war by using diplomatic methods. By using these methods, war should be ended and once again the economic condition of the countries can be restored.

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