Stock market today: Dow, S&P 500, Nasdaq futures sink after Trump targets allies with tariff threat over Greenland

Group 1: Market Reactions - US stock futures experienced significant declines, with Dow Jones Industrial Average futures down 1.3%, S&P 500 futures down 1.4%, and Nasdaq 100 futures down 1.7% as trade tensions escalated [1] - The market is reacting to President Trump's threat of imposing tariffs on imports from eight NATO countries, which could lead to retaliatory tariffs from the EU amounting to $108 billion [2] - The benchmark 10-year Treasury yield rose to just below 4.3%, reflecting a global slump in bonds influenced by concerns over Japan's economic policies [4] Group 2: Corporate Earnings Outlook - Investors are preparing for a busy earnings season, with key results expected from companies like Netflix, Intel, and Johnson & Johnson [6] - Analysts anticipate S&P 500 earnings growth of approximately 12% to 15% this year, but caution that negative sentiment towards US companies could lead to equal downside risks [6] Group 3: Legal and Economic Implications - The Supreme Court may soon rule on the constitutionality of Trump's use of the International Emergency Economic Powers Act to impose tariffs, with Treasury Secretary Scott Bessent suggesting it is unlikely the court will overturn this policy [5]