What if China and India became friends?

China’s rulers like to look down on India. They scorn its turbulent politics, its creaky infrastructure and its poverty. India has looked across with a combination of fear and envy, hoping in vain to be treated as an equal. Now the tectonics of the trans-Himalayan relationship are shifting. Recent border bloodshed suggests mounting hostility. But blossoming economic ties tell a different story that could trouble America and its allies.