Obeying Trump to Launch Nuclear Strike?

Adm. Scott Swift, the U.S. Pacific Fleet commander, said he would launch a nuclear attack against  a foreign country, if ordered by President Trump, stating that every member of the US military has sworn an oath to obey the Commander in Chief. This is the same reasoning which was employed by German officers for obeying Adolf Hitler. What is wrong with this rationale in the eyes of God and the Bible? Can a true Christian be a nationalist, defending his country, “whether right or wrong,” and fighting in his country’s wars?