Based on the map, why might korea have been better able to maintain its independence compared to vietnam?

The battle of sabine pass is important because? a) it was a stalemate between union and confederate armies. b) it resulted in the largest confederate casualty in the war. c) it marks the failed attempt of the union army to invade the confederate state of texas. d) it was won by the union soldiers and marked a turning point in the western front of the war.