所有这一切都是跨大西洋国家集团持续转型过程的其中一部分：由一系列专为防御某个已知入侵者设计的组织，转向应对某些更加灵活机动的威胁。
All of this is part of the transatlantic community’s continuing transformation from a set of organizations designed to defend territory against a known aggressor to something more flexible and dynamic.