The SDA church recommends its members they should serve their country in time of war as non combatants although some members do go into frontline service as combatants. SDAs have chaplains in the military Barry Black was a rear Admiral and was head of the chaplains in the US navvy. Barry Black then became head of chaplains in the US senate.
Some SDAs don't get involved in politics except in a referendum. Many SDAs do vote. The American Neurosurgeon Ben Carsons is an SDA and is running for president of the US this year.
There is no definite position among SDAs with these two questions.
All christians talk about Gods kingdom
All christians guard against fornication and sins which put them in a position of rebellion against God.
SDAs don't disfellowship call people apostates they simply DROP names from membership so as not to infer negativeness.
I was an SDA but am now an Anglican