The recent edition of the Economist, a liberal weekly, devoted two pieces to the phenomenon of extraterritoriality, that is application of domestic rules beyond the country’s shores. See here and here.
The extraterritoriality is by no means a new phenomenon. Competition law (or antitrust law, as it is called in the U.S.) was most likely the first area in which it has been relied on. The U.S. was its original enthusiast. Initially many countries opposed any such extraterritorial assertions by a variety of means—from diplomatic notes and amicus curiae interventions (see discussed here, if interested) to adopting legislation aimed to block the long-reach of U.S. law (see here). Nowadays, most developed countries rely to extraterritoriality in competition law whenever it is needed (see, for example, here and here).
Extraterritoriality is a rational unilateral response of the effected country to challenges posed by transnational activities which escape scrutiny in their home countries and/or at the multilateral level. Its continued relevance points to the need of further development of international collaboration. These are some of the topical issues which practical relevance continues– and which we are covering in the module in the context of competition law.
PS: I encourage any willing person to correct the Wikipedia entry on this topic. It mixes up two distinct concepts of extraterritoriality and exterritoriality. The former is a phenomenon of application of domestic laws beyond country’s shores. The latter refers certain diplomatic immunities enjoyed by foreign states and international organisations in a hosting jurisdiction. It does not help that Encyclopaedia Britannica mixes these two concepts as well (by talking about exterritoriality while using the term extraterritoriality, see here).