Maryland Gov. Martin O’Malley’s “millionaires’ tax” proved such a disaster that it had to be abandoned after a single year. But don’t think O’Malley has learned any lessons from that affair. He is back again, rifling through the pockets of Marylanders and finding new ways to kill the golden goose. This time, he has set his sights on taxing Internet sales. O’Malley’s 2008 millionaire surtax was intended to raise the income tax bill of wealthy families by 32 percent and raise an extra $106 million in revenue. Instead, it prompted one-third of Maryland’s top earners to leave the state, sending tax revenue plummeting by 22 percent. Instead of collecting that extra $106 million, O’Malley’s blunder actually cost the state $257 million. The Wall Street Journal’s analysis of federal tax-return data found that “Maryland lost $1 billion of its net tax base in 2008” from residents moving to other states. That means the millionaire tax is still costing local governments much-needed revenue.

O’Malley’s seemed to have learned his lesson in January, when his press secretary told CNN Money, “We can balance the budget through cuts and without new taxes.” Just four months later, however, the governor wrote a letter to state Comptroller Peter Franchot asking him to find out just how much sales tax revenue the state was supposedly losing to Internet sales. Since the study is being conducted by the Maryland Bureau of Revenue Estimates, it’s clearly only a matter of when — not if — O’Malley and his pals in Annapolis will try to get their sticky fingers on the growing Internet sales pie.