PARIS – The United States is widely recognized as possessing the deepest, most liquid, and most efficient capital markets in the world. America’s financial system supports efficient capital allocation, economic development, and job creation.

CAPE TOWN – At last, European leaders have revealed their top-secret plan for solving the euro’s crisis. And it is – drum roll – a version of the “Tobin tax,” a levy on financial transactions first suggested in 1972 by the Nobel laureate economist James Tobin.

If there is anyone who should be angered by Standard & Poor's raft of eurozone downgrades , it would seemingly be the prime minister of Italy, whose debt was cut two notches with a warning of more to come. But on the first trading day after the credit rating agency's verdict, Mario Monti – a respected economist who became Italy's technocratic premier after the resignation of Silvio Berlusconi in November – is buoyant.

RUSSELS – European policymakers like to extol the strength of the eurozone: relative to the United States, it has a much lower fiscal deficit (4% of GDP, compared to almost 10% for the US). Moreover, unlike the US, the eurozone does not have an external deficit, which means that the monetary union holds enough savings to finance all of its members’ budget deficits and resolve their debt problems.

World markets celebrated a successful summit of European leaders with a substantial rally, particularly in Europe. There is no doubt that European leaders made significant progress on key issues necessary to solve the Euro Crisis. However, they also left us with many intriguing questions, especially how they intend to lever up the European Financial Stability Facility (EFSF), the fund to support governments and financial institutions that suffer problems in accessing financial markets.

Dani Rodrik, Professor of International Political Economy at Harvard University, is the author of The Globalization Paradox: Democracy and the Future of the World Economy.

BRUSSELS – Once upon a time, there was a country plagued by large deficits, high inflation, and decades of economic stagnation. When economic problems once again became particularly acute, the country’s leadership embraced a radical approach to achieving price stability.

Kenneth Rogoff is Professor of Economics and Public Policy at Harvard University, and was formerly chief economist at the IMF.

HELSINKI—European Central Bank President Jean-Claude Trichet signaled a temporary pause in the ECB's path toward higher interest rates, a sign of caution as officials confront mounting problems along Europe's periphery.

The Portuguese hope to emulate the Beatles and get by with a little help from their friends, never mind that the €80 billion-€90 billion ($115 billion-$130 billion) of help they need hardly qualifies as "little."