A driver suspected of killing an 84-year-old World War II veteran in an early-morning hit-and-run crash on Veterans Day had his San Francisco Superior Court arraignment postponed today due to the unavailability of his attorney.Arthur Clark Jr., 20, of San Francisco, is charged with felony vehicular manslaughter, felony hit-and-run, and driving on a suspended license in connection with the Nov. 11 crash that killed Isaac Hudson.Clark’s attorney, Steve Olmo, was in trial today and Clark, standing in orange jail garb as members of Hudson’s family looked on, agreed to postpone his arraignment until Dec. 24. Bail remains at $1 million in the case.Hudson, a San Francisco resident, was killed when a 1990 Lexus struck his Ford Escort shortly after midnight at the intersection of Alemany Boulevard and Congdon Street in the city’s Outer Mission neighborhood.Witnesses saw three men run from the Lexus after the crash, police said.Investigators believe Clark was the driver based on witness accounts, evidence in Clark’s name found inside the abandoned Lexus, and a DNA match connecting him with a sample found on the car’s deployed airbag, according to the district attorney’s office. The car is registered to Clark’s girlfriend, prosecutors said.District attorney’s office spokesman Brian Buckelew said the driver of the Lexus is believed to have been at fault for the crash. Investigators estimate it was traveling at about 50 mph when it slammed into Hudson’s car.Clark was already in custody on an unrelated charge of marijuana possession for sale when the DNA hit came back on Dec. 3, Buckelew said. He had been arrested on the drug charge Nov.20.Clark is also on felony probation for weapons violations and has a no-bail hold for a probation violation.Hudson was a U.S. Army veteran who served in the Battle of Normandy, the Rhineland Campaign and the Ardennes Offensive, for which he received several service medals. He was honorably discharged in 1946.