How did nationalism threaten the existing political order of the nineteenth century?

4 answers

Is there something about this question you do not understand? What does your textbook say?
single most powerful European political ideology of the 19th and early 20th centuries

political outlook, nationalism was and is based on the relatively modern concept that a nation is composed of people who are joined together by the bonds of common language

as well as common customs, culture, and history
bonds should be administered by the same government, nationalists in the past and present contend that political and ethnic boundaries should coincide

belief that one is part of a nation, defined as a community with its own language, traditions, customs, and history that distinguish it from other nations and make it the primary focus of a person's loyalty and sense of identity
Okay, so how is this different from earlier ways of thinking? What was the existing political order? What was it based on? Military power? Religion? What?
The political order of the 19th century, at the time combined people of many nationalities who wanted their own governments.