Federal Reserve’s emergency loan and market-support programs could start to inadvertently subsidize unwise risk-taking. To avoid having taxpayers once again on the hook for Wall Street excesses, the government needs a clear strategy for winding the schemes down.For the short-term liquidity facilities, which are no longer urgently needed, the government should act sooner rather than later. The country’s massive borrowing requirements — an eye-popping $104 billion of notes is on offer this week alone — may push short-term interest rates up, making the Fed facilities attractive once again. If that happens, it may be harder for the government to snatch away the punch bowl.The Fed’s asset-backed security funding program is gaining steam and may eventually total as much as $1 trillion. It appears to have a good chance of reviving at least parts of the moribund securitization market. But again, the pricing and collateral requirements of the loans backing the ABS should be calibrated carefully to allow only those deals that would be viable under normal market conditions to cross the finish line.