JERUSALEM, Israel -- In Mohammed Morsi's first speech as Egypt's new president, he promised to represent all Egyptians.
After Morsi's defeat of former Prime Minister Ahmed Shafiq, the Muslim Brotherhood member has become the first Islamist president in Egypt's modern history.
Morsi, 60, said he carried a message of peace to the world, tried to reassure Egypt's Christian minority, and pledged to preserve Egypt's international agreements.
On Sunday, Morsi's supporters celebrated his victory in Cairo's Tahrir Square and throughout Egypt. In Gaza, next door, the Palestinian terror group Hamas -- an offshoot of the Muslim Brotherhood -- also celebrated his victory.
Morsi claims he wants to incorporate "moderate Islamic tendencies," but many Egyptians and others are concerned that he will lead Egypt toward an Islamist state.
"It's a very important development. Probably the significance will be recognized or seen later, but what transpired yesterday is radical Islam," Zvi Mazel, former Israeli ambassador to Egypt, told CBN News.
"Political Islam took the helm of the most important country, Egypt, and this is bad for Egypt, bad for the Middle East and also bad for Israel," he said.
The question here in Jerusalem is what Morsi's victory means for Israel.
Israeli officials are keeping a low profile. The Prime Minister's office released a statement that said they respect the results and look forward to cooperating with Egypt on the basis of their peace treaty.
Dore Gold, director of the Jerusalem Center for Public Affairs, told CBN News "the Muslim Brotherhood thoroughly rejects peace with Israel."
Gold believes Morsi's election puts Israel's 30-year peace treaty with Egypt in jeopardy.
"I would anticipate they will look for ways to wiggle out of peace," he predicted. "For example, in the Muslim Brotherhood, it's been suggested that they have a national referendum on whether the peace treaty should continue."
But right now, Morsi must deal with Egypt's military. Just before the election, the ruling council assumed sweeping new powers.
"We'll have to see how the struggle between the armed forces and the Muslim Brotherhood under the president will develop," Gold said.
The outcome of that struggle will have an enormous impact on Egypt, Israel, and the Middle East.