In a letter to Obama yesterday, Senate Majority Leader Harry Reid and three other top Democrats said Obama “must be willing to take any lawful steps to ensure that America does not break its promises and trigger a global economic crisis — without congressional approval, if necessary.”

The Democrats’ letter sharpens the dispute with Republicans over the borrowing limit, which the U.S. hit at year’s end. Amid Republican opposition to raising the debt ceiling without spending cuts, some Democrats have proposed invoking the Constitution’s 14th amendment and minting a platinum coin with a face value of $1 trillion to pay government bills. House Speaker John Boehner of Ohio and Senate Minority Leader Mitch McConnell of Kentucky, both Republicans, have said they will seek substantial spending cuts in exchange for any debt-ceiling increase. Boehner has said cuts must match or exceed the amount the ceiling is raised.

Obama must act on his own to prevent default “in the event that Republicans make good on their threat by failing to act, or by moving unilaterally to pass a debt-limit extension only as part of unbalanced or unreasonable legislation,” wrote Reid of Nevada and Senators Richard Durbin of Illinois, Charles Schumer of New York and Patty Murray of Washington. The administration doesn’t think the president has the power to unilaterally raise the limit under the Constitution’s 14th Amendment, an argument advanced by some congressional Democrats, including House Democratic leader Nancy Pelosi. (Bloomberg News1/12/13).