NEW YORK--(BUSINESS WIRE)--Fitch Ratings has affirmed the Insurer Financial Strength (IFS) ratings of The Northwestern Mutual Life Insurance Co. (Northwestern) and Northwestern Long Term Care Insurance Co. (NLTC), collectively referred to as Northwestern, at 'AAA'. Fitch also affirms Northwestern's Issuer Default Rating (IDR) at 'AA+' and surplus note rating at 'AA'. The Rating Outlook is Stable. KEY RATING DRIVERS Fitch's ratings reflect Northwestern's leading competitive position in the U.S.