Perhaps your better-positioned brow could clarify exactly how the involvement of a blockchain would solve WeChat's problem and make it easy for Americans to buy

Perhaps your better-positioned brow could clarify exactly how the involvement of a blockchain would solve WeChat's problem and make it easy for Americans to buy in? In particular, if it could be done, why isn't WeChat doing it? And if WeChat can't do it, why can WhatsApp do it?