Ellen Knickmeyer And Stephen Groves, The Associated Press WASHINGTON (AP) – South Korea n President Yoon Suk Yeol urged ever more strengthening of the U.S.-led security alliance against nuclear-armed North Korea on Thursday, drawing cheers from Congress as he saluted the “great American heroes” who helped preserve his country's democracy in the Korea n War. Democratic and Republicans lawmakers rose to their feet again and again to applaud during Yoon's address to a joint meeting of the House and Senate, in a speech that stressed security cooperation at a time of increased tension with both North Korea and China. Yoon…