ClimateWire: President Obama challenged the country last night to unify behind a “national mission” to reduce its reliance on oil and coal, using his first Oval Office address to pressure Congress into acting quickly on clean energy legislation. The primetime speech sought to confront stinging criticism around the president’s handling of the wayward oil spill in the Gulf of Mexico, an ongoing catastrophe that has stretched on for nearly two months, with crude still pouring from the open BP …