Throughout Europe’s debt crisis, Italy has largely managed to steer clear of the troubles that have engulfed its profligate Mediterranean neighbors.

But the contagion that started in the euro zone’s smaller countries is suddenly moving to some of its largest. As Greece teeters on the brink of a default, the game has changed: Investors are taking aim at any country suffering from a combination of high debt, slow growth and political dysfunction — and Italy has it all, in spades.

In recent days, Italy has become Europe’s next weak link after Greece, Ireland, Portugal and Spain, harmed in particular by a power struggle between Prime Minister Silvio Berlusconi and his finance minister, Giulio Tremonti. The dispute threatens to turn the euro zone’s third-largest economy, after Germany and France, into one of its biggest liabilities.

On Monday, the Italian government struggled to rein in the tensions, as fears rose that political paralysis could make it harder for Italy to embrace the austerity demanded by outsiders to reduce one of the highest debt levels in the world. European policy makers also sought to figure out how they would put out a bigger fire if Italy were to succumb.