NEW DELHI – As if to highlight that Asia’s biggest challenge is managing the rise of an increasingly assertive China, the Chinese government has unveiled plans to build large new dams on major rivers flowing to other countries. The decision by China’s State Council to ride roughshod over downstream countries’ concerns and proceed unilaterally shows that the main issue facing Asia is not readiness to accommodate China’s rise, but the need to persuade China’s leaders to institutionalize cooperation with neighboring countries.