This morning, Mitt Romney chose the backdrop of the USS Wisconsin, one of four members of the mighty Iowa class and a magnificent symbol of American power, to introduce Rep. Paul Ryan of Wisconsin as his running mate.  If Ryan becomes vice president, he will be the first member of the House of Representatives elected vice president since John Nance Garner, FDR’s running mate in 1932 and 1936.

Of course, Ryan is best known for his efforts to restrain the growth of the federal government, particularly entitlements.  His addition to the ticket thus represents a sharp contrast with the last congressman chosen to be the GOP’s vice presidential nominee, Jack Kemp, who famously derided a focus on budget cutting as “root canal economics.”  Ryan’s budget will certainly provide a target for the Obama campaign, which will try to take the focus off the dismal economy and stoke fears about what a Republican presidency would mean for those dependent on federal spending.  But Romney clearly believes that Ryan is the ideal candidate to appeal to growing anxiety about what our enormous and exploding debt portends for the future.

Ryan is the first Catholic to be put on the GOP’s national ticket since Barry Goldwater chose William Miller as his running mate in 1964, and he thus embodies the type of voter Romney will need to win to capture the White House.   It is difficult to see how Romney wins if he fails to win the Midwest or Catholics.  (Conversely, Ryan’s selection means that the GOP, the political home for a majority of America’s white Protestants, will run a ticket without a Protestant for the first time in its history).  It remains to be seen whether Ryan’s sometimes doctrinaire libertarianism will help Romney win those voters and the White House.