This first propaganda poster shows people what could happen if they didn't join to help their country's fight in the war. Which this probaly shows an extreme exageration as to what might have happened.
The second propanganda poster shows how the American people should be even more influnced to go into the war so that they can stop the enemy and protect the women and children.
The third propanganda poster shows how the Germans had control over other countries and armies during WWI.
The fourth propanganda poster shows Uncle Sam wanting the American people to do their part and help in the war. Its saying that it is in your hands as a country to pull together and defend the country's honor in the war.
This is a modern day propaganda poster and it shows how people think that our soldiers are over there in war now just for oil. It is really different to propaganda back during WWI.