| A | B |
| War of 1812 | Attempted to fight a three front War |
| War of 1812 | The prospect of attaining Canada thrust the US into a premature war |
| Mexican War | Wanted to purchase California - President Polk provoked use of force |
| Spanish-American War | President McKinley opposed war, people enthusiastic |
| WWI | US was prepared to remain neutral |
| WWI | Before the war, the US had less than half a million active troops - after they entered nearly 4.5 million were active |
| WWII | Able to signup a mass of people in a short time |
| Korean War | Truman removed MacArthur from his command |
| Vietnam War | Thousands fled to Canada to escape draft |
| ....WWII | US forced to declare war - tried to stay out due to home economic issues |