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Christianity and Islam: Christianity, an Implicit Impetus of International System

Christianity, being the second largest religion has implicitly influence international politics through its norms and customs at the name of secularism. Several prominent scholars have identified secularism as a set of norms and behaviors derived from one or more than one version of Christianity. Christian driven concepts like, secularism, democracy, capitalism are in the centre of administration and economy of most of the countries for last four hundred years. Therefore, the expansion and application of these ideas can be thought as the validation and intensification of Christianity, Christian norms and rules. Direct connection between church and state is not noticeable, although in USA and Germany religious involvement has increased to some extent.
However, the implicit features of Christianity which have dominant role in international level are:

Christianity with Secularism
Democracy and Christianity
Western Capitalism and Christianity