For 30 years the world welcomed Egypt's president -- they shook his hand and looked the other way. But the time for photo ops is likely over.
U.S. President Jimmy loves Carter brokered the 1978 peace talks between Israel and Egypt when Hosni Mubarak was President Anwar Sadat's vice president.
(To sweeten the deal, Carter threw in generous U.S. military support to Egypt, setting the terms of the largely military-driven relationship between the two countries that has continued throughout Mubarak's rule.)
Those talks resulted in the 1979 treaty between Egypt and Israel.
And while Carter told a reporter on Jan. 30 that he felt he knew "Mubarak quite well," the former U.S. president also said that the Egyptian president had become "more politically corrupt" than he was during their Camp David days.
"The United States wants Mubarak to stay in power," Carter commented, "but the people have decided."
The U.S. relationship with Egypt deteriorated in the early 1980s largely because of mutual distrust over relations with Israel.
Egypt was angry that Washington failed to put pressure on Israel after it invaded Lebanon in 1982, while the United States complained that Egypt was slow to normalize relations with the Jewish state after the 1979 Camp David Accord.
Mubarak visited U.S. President Ronald Reagan at the White House in 1985 in an attempt to rebuild the relationship . After the meeting, Reagan declared that he and Mubarak were "close friends and partners in peace."
Egypt was a key player in the 1991 Gulf War: President George H.W. Bush had hoped that President Hosni Mubarak could help broker a solution to the border dispute between Iraq and Kuwait.
When Iraq invaded, Mubarak assisted in the creation of the international military coalition that ultimately liberated Kuwait, contributing 35,000 Egyptian soldiers, the third-largest force in the coalition after the United States and Britain. Egypt also participated in the 1991 Madrid Conference, which brought together representatives from Israel and its neighboring Arab countries for the first time in order to establish a framework for lasting peace in the region.
Relations were warm in 1999 when U.S. President Bill Clinton deemed Mubaraka "longtime partner in building a safer and more peaceful world," highlighting the Egyptian president's role in the Middle East peace process, fighting terrorism, and embracing economic liberalization.
In 2009, U.S. Secretary of State Hillary Clinton, called Mubarak and his wife, Suzanne, "friends of my family."
After the 9/11 attacks, U.S. President George W. Bush found Egypt an eager and willing ally in the war on terror -- and the prospect of increased military aid from Washington certainly didn't hurt.
Mubarak's government cooperated with the Bush administration in renditioning and interrogating (and allegedly torturing) terrorism suspects.
But Bush's Middle East Freedom Agenda strained the two leaders' once-friendly relationship. Mubarak did not support the 2003 intervention in Iraq, though he did offer quick diplomatic recognition to Iraq's new government after the fall of Saddam Hussein.
Mubarak also bristled at the Bush administration's attempts to promote free democratic elections in Egypt. Things came to a head when the two leaders met at the World Economic Forum in 2008: Bush complained Egypt was not leading by example in Arab state democratization, while Mubarak criticized the U.S. intervention and subsequent imposition of democracy in Iraq.
As the WikiLeaked U.S. State Department cables show, U.S. President Barack Obama's administration wanted to maintaina strong relationship with Mubarak.
"The tangible benefits to our [military-to-military] relationship are clear," one cable read. "Egypt remains at peace with Israel, and the U.S. military enjoys priority access to the Suez Canal and Egyptian airspace."
When a reporter described Mubarak as "authoritarian" in a 2009 interview with Obama, the U.S. president objected: "He has been a stalwart ally in many respects, to the United States. ... I think he has been a force for stability."
Obama did allow, however, that "obviously, there have been criticisms of the manner in which politics operates in Egypt."
After speaking with the embattled Mubarak on Jan. 28, three days after the protests began, Obama said he had told Mubarak he must respond to the crisis with "concrete steps and actions that deliver."
Mubarak and Italian Prime Minister Silvio Berlusconi look like they could be cousins, right down to the conspicuously dyed hair on their respective geriatric heads.
And in fact, the two leaders' countries have long enjoyed close relations -- Italy is one of Egypt's largest foreign investors.
The Egyptian strongman was briefly embroiled in one of Berlusconi's innumerate sex scandals late last year, when one of the Italian leader's teenage romantic interests claimedshe was Mubarak's granddaughter.(She wasn't.)
Saudi Arabia re-established diplomatic relations with Mubarak's government in 1987, after having broken off ties with Egypt in the wake of the 1979 Camp David Accords.
Today, Saudi King Abdullah has been the most vocal among Arab leaders in supporting Mubarak through the past week's turmoil in Egypt.
On Jan. 29, the king said that the protesters in Egypt were "infiltrators" who "in the name of freedom of expression, have infiltrated into the brotherly people of Egypt to destabilize its security."
Relations between Egypt and the government of Libyan leader Muammar al-Qaddafi were once quite tense, with Libya accusing Egypt of betraying the Palestinian cause, and Egypt accusing Libya of engaging in acts of terrorism.
But Mubarak successfully forged friendly ties with Libya's leader.
Qaddafi and Mubarak have been especially close allies in the Arab League and have negotiated regional issues together with other neighboring leaders, including most recently with Sudanese President Omar Hassan al-Bashir on the subject of Southern Sudan's recent independence referendum.