what do you think should be done with people who publically shun the armed forces of their country of residence at a home coming parade, calling them terorists, cowards and such?
That would depend on the country. In the United States they have every right to do so. Thoreau gave a scathing description on what sort of man a Marine was in his "Civil Disobedience". I suppose at one point some reactionary would accuse him of alternative loyalties and advocate his expulsion from the nation, much like Mark Twain's attacks on the rising tide of American Imperialism. Fortunately such forces did not succeed and now they stand as iconic figures of America political thought. One of the high points of an advanced liberal democracy is that the armed forces are not sacrosanct, nor are expansionist agendas. The idea that Muslims ought to leave because they refuse to participate in the hegemonic neo colonialism laying waste to the Muslim world is simply appalling. If it was the 1940's and the UK was facing an existential threat from a foreign power I would agree that every citizen had a duty to help defend their land and populace from such a threat. That is not the case today though.