Foreign policy: It's a complex, multifactoral matter, often difficult for the layman to understand. From the AP:
The United States offered Israel an unprecedented $30 billion of military aid over 10 years on Thursday, bolstering its closest Mideast ally and ensuring the state's military edge over its neighbors long into the future. The package was meant in part to offset U.S. plans to offer Saudi Arabia advanced weapons and air systems that would greatly improve the Arab country's air force.
Link via Rational Review.