10 things you need to know before the opening bell (SPY, SPX, QQQ, DIA, TSLA)

Here is what you need to know.Trump's trade war is sending the S&P 500 toward its worst December in 16 years. The S&P 500 has fallen 4.6% in December and is on track for its worst closing month of the year since 2002.
China warns of 'grave consequences' if Huawei's CFO isn't released. China summoned US Ambassador Terry Branstad to Beijing to protest Canada's detention of Huawei CFO Meng Wanzhou and warned that it would take further steps based on the US's response, the Associated Press