这一自主加入方针受到了一些批评，但计划应该被归为“自愿”还是“强制”无关紧要，因为国际协定一般只适用于决定加入其中的主权国家。
This opt-in approach has some critics, but whether a program is categorized as “voluntary” or “mandatory” is beside the point, because international accords generally apply only to the sovereign countries that have decided to join them.