The White House. Washington. DC. DaR MR. PRESIDENT. I write to voice my grave concern at the possibility that Yasser Arafat. the head of the terrorist Palestine Liberation Organization. mayupon his requestbe granted a visa to visit the United States for the purpose of addressing the United Nations. There is no question In my mind. Mr. President. that granting a visa to Mr. Arafat will undermine all you have done to pro. mote the peace process In the Middle East over the last nine months. Mr. Arafat heads an organization that still supports and engages in terrorist activities. including numerous assassinations.