Stocks Rally on First Trading Day of 2017; Trump Tweet Slams GM

U.S. stocks rallied early Tuesday, the first trading session of 2017, building on last year's gains. President-elect Donald Trump took to Twitter to slam General Motors (GM) - Get Report for producing its Cruze model in Mexico. Trump reiterated the need for a "border tax" in order to keep manufacturing jobs in the U.S. General Motors responded saying only its Cruze hatchback vehicle, that is sold overseas, is made in Mexico. U.S.-sold Cruze models are made in Ohio. Last month, Trump tweeted about Boeing (BA) - Get Report and Lockheed Martin (LMT) - Get Report . Oil prices rose to an 18-month high as production cuts between OPEC and non-OPEC members took effect. Brent crude eclipsed $58 a barrel. The cuts were agreed to in December. Twitter (TWTR) - Get Report shares were in focus after its China head Kathy Chen stepped down after only eight months on the job. Twitter is blocked in China. This is the latest executive to leave Twitter. Its chief technology officer and chief operating office departed in late 2016.