Which is an example of a union strategy that took advantage of a confederate weekness

The Union used its number of ships to keep the south from exporting or importing its goods to foreign countries. It also used the ships to spread slave-revolt propaganda to convince European countries to not to trade with the South so they'll be economically weak to provide their soldiers with nessecary equipment such as weapons, food, and clothing. The union also used its wealth to buy southern loyalties to block south' sports to weaken confederates further more. Also, the North had railroads which the government bought from different companies to provide transportation to their men faster along with weapons. They also had many inventors who came up with gadgets and codes to help the army.