Remember the Maine
This is to stimulate people at the time to join the war. The bottom of the ship says, "Join the war. Avoid neutrality." The ship is The Maine, which was apparently destroyed by "Spain".
This poster shows a women thinking of two types of men, the muscular soldier and the scrawny worker. This implies that she would obviously choose the soldier, promting more men to join the army.
The feast is encouraging people to reconsider what they eat, and how much they consume. It promotes citizens to lower their suppply of food and save it for the soldier.