U.S. Sen. Al Franken is urging the nation’s top credit and debit card companies to reassess their security measures after a series of data breaches that have comprised the personal information of millions of consumers.

In letters to card issuers Bank of America, Capitol One, Citigroup, JPMorgan Chase, Wells Fargo and networks Visa, MasterCard, American Express and Discover, Franken questioned why the United States hasn’t abandoned the magnetic strips on cards that make American consumers more vulnerable to hacking attacks.

Most other industrialized nations use more secure technology -- credit cards that have embedded computer chip and PIN-number systems for purchases.

“I hope to open a dialogue about what can be done to protect cardholder data and make it more difficult to commit fraud,” Franken wrote.

“Recent data breaches at Target, Neiman Marcus, and other companies make it clear to me that we’re dealing with a systemic security problem. Credit and debit card security is an obvious part of that.”