Ireland's decision to guarantee all bank deposits will contribute to the demise of the single European currency, because it will erode the euro's credibility if it's allowed to go ahead, Hugh Hendry, chief investment officer and Partner at Eclectica Fund, told CNBC on Thursday. The plan pledges to guarantee the liabilities of six Irish-owned banks totaling some 400 billion euros ($565 billion), more than twice the country's annual gross domestic product. "The decision, if left to stand … my prophecy is it will bring down the currency. The euro is not a tenable currency if you have politicians making such decisions. The reality is there is no such thing as a free lunch," Hendry told "Squawk Box Europe." "If I was German, I would say give me back my Deutschmarks," he added. Why Ireland Will Destroy the Euro - Economy * Europe * News * Story - CNBC.com Why would this be important to U.S. Investors? The Financial Planning landscape over the past decade has seen a greater number of U.S. investors pour more money into European based assets and securities. It really also drives home the point that we by far are not the only country dealing with an over leveraged property debt crisis. This is not just a U.S. crisis, it is a global crisis.