What is the maximum acceptable long-term interest rate for Italy?

All crises and recessions make investors fear that a public debt crisis will emerge in Italy that would threaten the integrity of the euro. This is due to Italy's special situation: very high public debt ratio, zero potential growth in real terms. The ECB must therefore continuously prevent an excessive rise in Italy's long-term interest rate that would lead to fiscal insolvency and a debt crisis for Italy. We try to estimate the maximum long-term interest rate on Italy's public debt, taking into account the fiscal solvency constraint, but also the fact that the only relevant public debt is the debt not held by the central bank. This maximum long-term interest rate is around 2.2%; it would be 2% if the central bank had not held Italian public debt. The only way for the Italian long-term interest rate to remain below this level is for Italy to continue to benefit from the ECB's protection and the mutualisation of public debt at the European level - which is something the 50% of Italians who want Italy to leave the European Union should understand.