You do have a good point there. He opened the can of worms, not us.
You are right....and here is another example of the Kerry campaign's attempts to paint Bush as someone who did something wrong....
From the John Kerry for President website
One sharp distinction between Kerry and Bush is the way they chose to deal with military service during the Vietnam War.Kerry is "in error" when he says his campaign is not actively promoting the issue of Bush serving in the Guard. (I am putting it kindly when I say this is a Kerry-"error.")Bush would decide to avoid active service by allowing his father to pull strings to get him into the National Guard in Texas, while Kerry volunteered for the Navy and asked to be sent to Vietnam