Global warming concerns everyone on earth and there can be no exception to it. It does not help to play politics on this as this is bound to affect everyone in the long run.
India should adopt a pro-active role of embracing greener methods of economic progress. In any case, there'll be a huge cost burden of switching over at a later stage, so why not now instead of later.
India should adopt a middle path of electing to embrace such climate-friendly policies as do not weigh heavily on economic growth. Yes, US is a much larger polluter and we don't have to be shy to state that loud in front of Americans as much as they seem to remind us loud.