European countries and major corporations are pressuring President Donald Trump to remain in the Paris climate agreement despite his promises on the campaign trail to withdraw the United States from the Obama-era deal that never gained congressional approval.The Trump administration so far is sticking with being undecided—at least until Trump returns to the United States from his first foreign trip, where on Friday, he’s meeting with Group of Seven ally countries, which support the agreement.Back home, the pressure is growing from multinational corporations, even the energy sector, which have opposed stricter limitations on carbon.Exxon Mobil Corp., once run by Trump’s...