It's only like 20 minutes longer driving time and doesn't involve toll roads. DC is much closer to State College than you'd think it would be. Plus picking the DC airports over Philly gave you way more options. Pittsburgh is close to an hour less of a drive than DC or Philly, but good luck flying anywhere out of there any more. And MDT (Harrisburg) is worthless in every way, so that's right out.
Just out of curiosity, I looked into your plan:
The drive from State College to the nearest useful train station (the drive actually passes a stop on the Pennsylvanian and State College is within 25 straightline miles of two others, but those are not useful) is 94 minutes to Harrisburg.
I live in the vicinity of Dulles Airport and have driven on the Bud Shuster highway (aka I-99) pass State College (albeit some years back), so I am familiar with the drive. Checking the maps, State College to Dulles Airport is around 3-1/2 hours and 210 miles by car, depending on the route. That is a long drive and not cheap, when the full cost of the drive is added up. Say, ~$100 each way, using a cost basis lower than the IRS per mile number. JFK Airport is not all that much further at ~260 miles and of course would likely offer even more international destinations that Dulles Airport. State College is rather isolated from the big cities, out there in central PA.
An option would be to drive or get a bus for the 32 miles to Lewistown, take the Pennsylvanian to NYP in a relaxing 5.5 hour trip, and then LIRR & Air Train to JFK. Or take a bus from State College to Harrisburg (I assume there are such buses) and a Keystone at roughly 3:15 trip time to NYP. Yes, taking Amtrak to BWI or WAS, then to Dulles is not convenient without the not likely to return soon Harrisburg to Baltimore connection, but it can be done. My reaction is mainly that State College to Dulles Airport is a really long way to drive just to get to the lovely Dulles Airport for international flights over the other travel options.