The constant resistance of the regulating agencies at the time prevented PANAM from establishing any meaningful domestic network to feed their International traffic and eventually resulted in the ill fated National acquisition. The U.S. Government was not willing to put it's support behind one or two National carriers as other countries did and at that time had opened International flights to everyone. While before PA and TW were about the only and dominant U.S. carriers serving Europe, all of a sudden one could see Eastern, Piedmont, TWA, Braniff, Continental, Western, National, Northwest, Air Florida, People Express as well as World Airways, Capital and Transamerica amongst others at the gates in LHR ( I can't remember AA, DL and UA were in the mix then ). This effectively cut off the lifeline to the airline which had its major operations concentrated at JFK. Combine this with an inept management team and disaster was imminent.