There is hardly a more resolute supporter of Israel in Congress than Rep. Henry Hyde, the venerable chairman of the House International Relations Committee. That is why his March 25 letter to Secretary of State Colin Powell is so important. It is a plea to deflect Prime Minister Ariel Sharon's wall around the Holy Land from its planned position blocking the Scriptural pathway of Jesus Christ. ''I fear that important religious sites will become museums for commercial purposes and will no longer be maintained as places of spiritual worship shared by billions across the world,'' Hyde, a prominent Roman Catholic...