irony of obama's accomplishments

Correct me if I’m wrong, but one of the ‘big’ pieces of legislation Joe Biden credited Obama with involved a bill concerning loose nuclear weapons that was received a 98-0 vote in the senate and was signed by George Bush. So, the VP has acknowledged that Obama’s major accomplishments occurred when he cooperated with Bush. How does that jibe with Obama’s attacking McCain for agreeing with bush 90% of the time? I guess Biden would argue Obama could have accomplished more by going along with Bush more often?