Alright. Lets go through this initial question, conflict by conflict
World War One- Lusitania threw us physically into a war we were already fighting economically
World War Two- We defended ourselves. After declaring war on Japan because of Pearl Harbor, Germany then declared war on us, not us on Germany
Korea- Under the surrender of Japan in WW2, and the stop of Domino Theory, we had to intervene or else East Asia wwould be Communist, including Japan
Vietnam- Started by aiding French, carried on
Cold War- started after WW2
Grenada- Didnt want another communist island country so close to U.S. Soil, and Cuban troops were aiding the overthrow. On top of that US needed to evac US citizens or else it would have been Iran Hostages II- Carribean Crisis
Panama- Noriega was a cruel cruel person. Deserved it
Desert Storm- UN Sanctioned, protected Kuwait and Saudi Arabia from Annexhation, also protected Israel.
Bosnia- Stopped Genocide
Somalia- Stopped Ethnic Cleansing/Genocide
Afghanistan- Rooted out the terrorists who initiated the war in a similar way to Pearl harbor in 9/11.
Iraq- Carry on from Desert Storm, the war never stopped (Op. Desert Fox, OSW, ONW)