diplomacy

As nouns the difference between diplomacy and diplomatism

is that diplomacy is the art and practice of conducting international relations by negotiating alliances, treaties, agreements etc., bilaterally or multilaterally, between states and sometimes international organisms, or even between polities with varying status, such as those of monarchs and their princely vassals while diplomatism is diplomacy.

As a noun diplomacy

is the art and practice of conducting international relations by negotiating]] alliances, [[treaty|treaties, agreements etc, bilaterally or multilaterally, between states and sometimes international organisms, or even between polities with varying status, such as those of monarchs and their princely vassals.

As an adjective bismarckian is

of or pertaining to (otto von bismarck) (1815-1898), german statesman associated with antisocialism, complex diplomacy and the creation of the welfare state.