Just like abortion or gay marriage, it's a small wedge issue designed to distract from economy or war.
Mccain looks like shit on both of those, but he looks great on patriotism. So, his team will try to make the presidential debate about patriotism, not about the economy or the war (borrowing), the issues that actually affect us.
They're both US Senators. They both love this country and serve her. Both could be far richer outside of D.C. in the private sector, but both choose public service. To choose your candidate over patriotism is silly.