() the practice of making it difficult for foreign companies to do business in your country, for example by taxing their goods, in order to protect your own industry 闭关政策；锁国政策➡protectionism
the practice of keeping things secret and not allowing the media or anyone else to know anything about them 封锁政策，隔离政策（对某事严守秘密，不让媒体或任何人知道）