The concept of concurrent powers responds to the fact that many actions are necessary to serve the people at both the federal and state levels. Most notably, the power to impose and collect taxes is needed in order to raise money needed to provide police and fire departments, and to maintain highways, parks, and other public facilities.
They were forced to surrender because when they went to war, The French resulted in a French repulse, and to give in to Alexandria.
If the border with Laos had been closed and North Vietnam had not been able to operate in the country, the communist side would not have been able to stock up on resources, men, ammunition, weapons, food and medicine through the HoChi Minh Trail.
Therefore, the forces of the North that were fighting in South Vietnam would have been out of supply, and their defeat would have been imminent.
They later became the United States constitution
