U.S. customs agents have started collecting President Donald Trump's 10% tariff on imports, with higher levies on goods from 57 larger trading partners set to begin next week. The tariffs have caused a $5 trillion loss in S&P 500 value and have impacted global stock markets. Countries like Australia, Britain, and Saudi Arabia are among those facing immediate tariffs, while exemptions include crude oil, pharmaceuticals, and semiconductors. China has responded to the tariffs by imposing countermeasures and stating that 'the market has spoken.' World leaders are hoping to strike a deal with Trump to avoid economic fallout, while some are considering countermeasures.