The USA needs no reason for wars. If you like to do a war you do it. The only problem is to find out who this "you" is who always likes to do wars. The holy U-Satana?
It's by the way really funny that the "great" USA under Donald Trump is not able to protect the own borders and needs the help of their two neighbors to do so.
The border to Mexico is about 3145 km and the border to Canada is 8891 kilometers - together this are 12,000 km. The size of the USA is about 10 million square kilometers. 833 squarekilometer/kilometer.
| Dänemark | 68 |
| Niederlande | 576 |
| Belgien | 204 |
| Luxemburg | 136 |
| Frankreich | 455 |
| Schweiz (mit Enklave Büsingen, ohne Obersee des Bodensees) | 333 |
| Österreich (ohne Bodensee) | 817 |
| Tschechische Republik | 817 |
| Polen | 469 |
| Insgesamt | 3 876 |
The border of Germany with 9 neighbors is 3876 km. The size is ~360.000 km^2 (3.5% of the size of the USA). This is about 93 squarekilometer/kilometer. So to protect our borders would be 9 times more difficult. But we could do so whenever we will like to do so. Our problem are not our borders - our problem are the EU-borders and a wrong asylum policy. Example: 80% of the refugees in Sweden go on vacation to their former home countries from which they are supposedly fleeing because they are politically persecuted there.