The prevalent approach suggests that constitutions are silent about secession and may even implicitly allow it. But an examination of world constitutions reveals that the overwhelming majority of countries vigorously protect territorial integrity. This article explains how democracies have been able to conceal their fight against secessionists, by creating a large gap between “the law on the books“ and “the law as practiced.“ In fact, democracies employ the most unconventional constitutional weapons to fight against secession. These include a ban on secessionist political parties from participating at elections and a constitutional eternity clause that makes territorial integrity an eternal value. Countries‘ total prohibition on secession may be explained on strategic as well as principled constitutional law considerations. The Canadian landmark “Reference re Secession of Quebec“ decision‘s precedential value for world constitutionalism must thus be qualified.