Describe some factors that eventually led to the united states entering world war one

There are 3 main factors that led to the US joining World War 1.

1. The Zimmerman Note

2. The sinking of the Lusitania

3. Unrestricted submarine warfare

The Zimmerman Note angered Americans because it was Germany, going behind the US's back asking for Mexico's help- saying that if they started a war with the US, then Germany would help it repossess some territory. If America was focused on a war against Mexico, it most likely wouldn't have joined WW1, or would've been as powerful.

The Lusitania was a British passenger ship that had Americans on it. Germans sunk it, and the people on board died. Germany claimed that it had contained munitions, but Britain denied it- only much later did people prove that there were actually weapons/supplies. Either way, whenever Americans die, Americans get mad.

Unrestricted submarine warfare is mainly just an immoral practice- sinking any ship in sight, without stopping it and confirming civilians.

I hope this helped!