Despite the huge sums expended to write down Greece’s foreign debt, there has been an outcry of censure against “interference” with the country’s national sovereignty. True, in exchange for considerable European aid, Greece’s ability to maneuver independently will be limited. But are complaints that Greek sovereignty has been severely impaired justified?The idea of a nation-state’s sovereignty is rooted in the seventeenth-century Treaty of Westphalia, which embraced non-interference by external agents in states’ domestic affairs as the guiding principle of international relations. But, taken to its logical extreme, national sovereignty would require the complete physical and social isolation of states from one another. Indeed, an excessive emphasis on national sovereignty leads to serious problems: after all, any international agreement, whether political or economic, entails a certain transfer of sovereignty.Europe’s aid to Greece is an example of a cooperative agreement whereby the various parties negotiate with the others’ interests in mind. Greece asked its fellow European Union members for help, and they have obliged with an enormous amount of aid. In addition to €130 billion in loans (more than 40% of Greek GDP, on top of the €110 billion loaned to Greece in 2010), a 50% “haircut” has been imposed on Greece’s private creditors, and the European Central Bank has waived expected returns on its holdings of Greek bonds.Regardless of whether this is technically and economically the best solution to Greece’s problem, it is logical that the EU participated in designing it. Participating in the collective life of the international community of states implies bearing others in mind and, when necessary, giving up certain prerogatives of sovereignty.For example, when Spain decided to join the World Trade Organization, it ceded sovereignty by accepting the WTO’s rules and regulations. It had to abandon commercially preferential treatment to some countries and treat all WTO members alike. Spain accepted this in exchange for being able to trade on equal terms with the rest of the world. British sociologist Anthony Giddens rightly describes such examples as cases of integration or union in exchange for global influence. States cooperate because it is advantageous for them to do so, but at the same time they lose control over certain internal matters. They shift from unilateral to cooperative decision-making.Whether this is a violation of sovereignty depends on our conception of sovereignty. As with the concept of individual freedom, national sovereignty depends on how its components are defined. In his classic On Liberty, John Stuart Mill used the “harm principle” to express the view that a person’s individual liberty could be limited only in order to protect others and avoid harm. The debate consists in how we define “harm” to others.In the same way, the debate about the meaning of national sovereignty consists in what we consider “domestic” matters. Depending on where we place the emphasis and how wide our focus is, we prioritize either a “global” (or at least “federal”) dimension to sovereignty, or a “national” dimension.The EU seems to represent a halfway point between these two conceptions of sovereignty. But it is becoming increasingly difficult to determine the difference between purely domestic matters and those that require international collective action.Globalization has made frontiers more porous. We see how one country’s policies, whether pertaining to work, the environment, public health, taxation, or myriad other issues, can have a direct impact on others. And we see such interdependence even more clearly in their economic performance: China’s annual GDP growth rate, for example, will slow by two percentage points this year, owing to sluggishness in the United States and the EU.Likewise, more countries (and more varied in their character and historical trajectory) are emerging strongly on the global scene: Brazil’s GDP recently surpassed that of the United Kingdom. Their emergence holds important implications for global governance at a time when the imbalance between existing problems/threats and the means available to states to guarantee their citizens’ safety increases.On a global scale, this complex and interdependent world needs an organization of states and structures of governance oriented towards responsible dialogue, the aim being to mitigate abuses of power and defend global public assets. Without such structures, the world risks a competitive and disorderly race to the bottom among states – as often occurs with taxation – together with a protectionist backlash. History has shown that such developments often lead to disastrous conflicts.On the European level, legitimacy is essential and – let’s be realistic – won’t be achieved unless and until Europeans overcome certain antiquated ideas about sovereignty. Paradoxically, when the crisis struck, the EU was criticized for its lack of integration. Now that it seeks to advance in that direction, the Union is accused of crimping national sovereignty.Citizens must have the feeling that the institutions that govern them account for their interests and make them part of the decision-making process, which implies a union based on rules rather than power. The fact that the EU does not instantly have all of the answers to a problem does not mean that it has no future. The EU is a new and marvellous experiment, which, as with all experiments, entails a degree of uncertainty. But that should not make us ignore the opportunity cost of a more “national” conception of sovereignty.Indeed, the dynamics of interdependence have become well established – so much so that they cannot be reversed. To adhere to a narrow Westphalian concept of sovereignty in this world is an unwise anachronism at best, and a dangerous gamble at worst.The poet Jose Angel Valente might call this a desire “…to wait for History to wind the clocks and return us to the time in which we would wish everything could start.” But, in the prosaic world of the here and now, the concept of sovereignty has already moved on.Javier Solana, former Secretary-General of NATO and EU High Representative for the Common Foreign and Security Policy, is Distinguished Senior Fellow in Foreign Policy at the Brookings Institution and President of the ESADE Center for Global Economy and Geopolitics. Copyright: Project Syndicate, 2012.