More than 60 years later and a few pounds heavier, Diehl was having a more enjoyable afternoon, along with about 40 members of his family and a few hundred others who gathered at the Tayamentasachta Environmental Center for a day of patriotic fun.
Russ Clever acted as Pied Piper for about two dozen participants in the children's parade, with one girl dressed as Lady Liberty and another group paddling a cardboard boat across an imaginary Delaware River.
Three families took part in the Most Patriotic Family Contest, including a large contingent of Diehl's relatives.
Emcee Frank Mowen asked for a round of applause for each family to determine the winner, but it was judged too close to call.
"It's a three-way tie, so all of them get prizes," Mowen said.
Families arranged themselves in the shade of Tayamentasachta's towering trees to escape the July sun. The schedule of events included patriotic music and readings, a ventriloquist, a magician, lunch served by Cub Scouts, a peanut and candy scramble sponsored by the American Legion, and watermelons supplied by the VFW.
While the Fourth of July for some is about having fun, it also is about remembering those who have made sacrifices for the country, and Mowen asked all attending veterans to stand and be recognized.
"This little town has had people in just about every war we've ever had and the veterans just don't get enough credit," Mowen said.
"There's a lot of people that take freedom ... Well, they think it's just there," said Diehl, who escaped with eight other men on May 7, 1945, the day before the war in Europe ended.
Freedom was short-lived for three of them, killed by the Russian fighter planes that attacked the column of prisoners escorted by Nazi guards.
Diehl said he saw men reduced to tears twice during the ordeal. The first time was when they surrendered and German soldiers went through their wallets, tearing up family photos.
The second time was when the liberated soldiers arrived at an American air base in Pilsen, Czechoslovakia.
"There was the biggest flagpole and biggest flag I'd ever seen," Diehl said.
"Yeah, July Fourth means a lot to me," he said.