| UNION CITY, California
UNION CITY, California Republican U.S. presidential candidate John McCain opened a new line of attack against Democratic front-runner Barack Obama on Thursday, taking aim at Obama's lack of military service.
McCain, a former Navy pilot and prisoner of war in Vietnam, struck back after Obama criticized McCain on the U.S. Senate floor in Washington for opposing legislation that would give expanded benefits to military veterans.
"It is typical, but no less offensive, that Senator Obama uses the Senate floor to take cheap shots at an opponent and easy advantage of an issue he has less than zero understanding of," said McCain, who was not present for the Senate vote because he was campaigning in California.
The Senate easily approved legislation that the Bush administration and some Republicans, including McCain, say is so generous it could encourage people to leave the military to take advantage of the benefits to get a college education, at a time of wars in Iraq and Afghanistan
In his Senate speech, Obama said he respected McCain's military service.
"But I can't understand why he would line up behind the president in opposition" to the legislation, Obama said.
McCain has clinched the Republican presidential nomination and has been stepping up his criticism in recent days of Obama in anticipation of a general election battle in November. But in this latest rash of attacks he had not mentioned until now Obama's lack of service in the military.
McCain said he appreciated the role that a former Vietnam veteran, Virginia Democratic Sen. Jim Webb, had played in developing the legislation aimed at helping veterans gain a college education and said the approach he supports differed only slightly.
"And I take a backseat to no one in my affection, respect and devotion to veterans. And I will not accept from Senator Obama, who did not feel it was his responsibility to serve our country in uniform, any lectures on my regard for those who did," McCain said.
McCain's status as a war hero who spent 5 1/2 years in a Vietnam prisoner of war camp is a major selling point of his candidacy for the November election, and many veterans strongly back him.
McCain's campaign issued the statement as the Arizona senator campaigned in California's Silicon Valley, attending an economic discussion with California Gov. Arnold Schwarzenegger and local business leaders.
At that event, McCain criticized both Obama and his Democratic rival, New York Sen. Hillary Clinton, for pledging to renegotiate the North American Free Trade Agreement, the U.S-Mexico-Canada pact that labor groups blame for outsourcing of U.S. jobs but which Republicans believe has been beneficial.
He has repeatedly accused Obama of inexperience and naivete on foreign policy, after Obama said he would hold direct talks without preconditions with leaders of hostile nations such as Iran and North Korea.
(Additional reporting by Thomas Ferraro; editing by Vicki Allen and Jackie Frank)
(To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at blogs.reuters.com/trail08/)