This could have happened if Germany made the bad decision to continue unrestricted submarine warfare. Luckily for the Germans, the German government realized the negative repercussions of such a choice. As we all know, Germany won the war through a successful spring offensive after gaining much needed resources from the new lands acquired in the treaty of Brest-Litovsk. So, here's my question: what if Germany continued unrestricted submarine warfare, which could get the US in the war?