Reader Mail: Should I Borrow Money from Retirement?

I’ve currently got two credit cards with balances: one with $5,500 (interest rate is 9.9%) and one with $1,700 (with a 20.99% interest rate). I’ve got about $4,000 in my Roth IRA, none of which is invested. I’m trying to figure out if it’s worthwhile to withdraw the $1,700 from my IRA to pay down the higher-interest credit card and focus all my monthly payments on the lower-interest one. I’ve always been told “never borrow against your retirement,” but it seems that this might be a good idea. Help?! — N.C.