Donald Trump’s defense lawyer may have committed a ruinous blunder during his closing argument. Attorney Todd Blanche characterized former Trump lawyer Michael Cohen, who was a key witness for the prosecution, as dishonest and untrustworthy but portrayed former National Enquirer publisher David Pecker as truthful — and MSNBC legal analyst Lisa Rubin said that was essentially a gift to prosecutors. “Todd Blanche just painted David Pecker as a truth teller in marked contrast to his portrayal of Michael Cohen,” Rubin posted on X. “If I am prosecutor Josh Steinglass, I just did a happy dance.” Wan…