Who are the Egyptian protestors screaming they hate and want gone? President Mubarak. Who has been President Mubarak's biggest friend and supporter with aid and diplomatic politesse? The United States. Why? Because he opposed the Islamists and supported the hated Camp David accord with Israel.
We are the friend of those Egyptian protesters' enemy Mubarak, so we are also their enemy. That isn't rocket science. It is elementary political science.