see here, when DC advertised this issue in their other mags, they highlighted the impossible nature of this story. "How can this be possible? Batman and Sgt. Rock together!" The answer is that anything's possible in a Bob Haney story. Batman probably teamed up with Abe Lincoln in a non-time travel story by Haney at some point.
Our tale begins with the curator of a museum informing Bruce that a World War II artifact is being claimed by someone with a German accent. As Bruce and his friend inspect the piece, a German confronts them with a luger, pistol-whipping the curator:
Let's be generous to Haney and say that he's 23 when he meets Churchill. That would make him 48 in 1969. Even as a teenager at the time, I knew that was ridiculous.
And don't get me wrong; I don't have any problem with Golden Age stories that show Batman fighting Nazis. But surely we can all accept that if he were to fight them today it would either have to be modern Nazis or some sort of time travel story? It wasn't much more credible in 1969 than it is today.
Anyway, back to the story. Bruce catches a lift with Easy Company, which is assigned to blow up a bridge just prior to the invasion. En route they run into a Luftwaffe fighter, but Bruce acts quickly:
Flash forward to 1969 again. Can you guess who saves Bruce from Von Stauffen?
Notorious, starring Cary Grant and Ingrid Bergman. In that movie, the stuff in the bottles turns out to have been uranium.