The stock markets are already reacting to Trump's intention to add additional tariffs. And this time, they're signaling a much wider impact. Trump's tweets were closely followed by sharp drops on the trading floor. The U.S. stocks started good but ended on the low side. The S&P 500, which had been up by as much as 1.1 percent, slumped to close 0.9 percent lower following the announcement. The Nasdaq Composite saw a 1.5 percent gain turn into a 0.8 percent decline. These losses extend beyond the stock market. A rise in consumer prices is being compounded by several other economic factors. Data published by the Institute of Supply Management's monthly index of manufacturing activity found last month's manufacturing to be at a three-year low. Just one of the many boiling effects of Trump's trade war.