The US Patriot missile stockpile, a key air defense system, has fallen below 1,700 due to a potential war with Iran. This level is estimated to take over two years to replenish considering the production rate. The US moved Patriot missiles from Asia to the Middle East to support operations against Iran, leading to growing security concerns among allies such as South Korea and Japan. The shortage of US weapons is also a cause for concern for Russia and China, raising questions about the military strength of Western nations.