The Sum of All Fears is a political thriller novel, written by Tom Clancy and released on August 14, 1991. Serving as the sequel to Clear and Present Danger (1989), main character Jack Ryan, who is now the Deputy Director of Central Intelligence, tries to stop a crisis concerning the Middle East peace process where Palestinian and former East German terrorists conspire to bring the United States and Soviet Union into nuclear war. It debuted at number one on the New York Times bestseller list. A film adaptation, which is a reboot of the Jack Ryan film series and starring Ben Affleck as the younger iteration of the CIA analyst, was released on May 31, 2002.

Plot

During the first day of the Yom Kippur War, the Israeli Defense Force (I.D.F.) prepares to conduct a tactical nuclear strike to stave off defeat. The necessity for the strike is averted, but an Israeli Mark 12 nuclear bomb is accidentally left on an A-4 Skyhawk attack aircraft flown by Captain Mutti Zadin; which is subsequently shot down over Syria ,near Kafr Shams. The nuclear weapon is lost, buried in the field of a Druze farmer. Eighteen years later, an Israeli police captain (coincidentally the brother of the downed pilot) converts to a fundamentalist sect of Hasidic Judaism after discovering his wife had an extramarital affair and attempts to instigate a violent demonstration of Palestinians at the Temple Mount. When the demonstrators unexpectedly conduct a peaceful protest, Zadin orders the police to fire tear gas and rubber bullets at the protesters anyway. Captain Zadin then kills the leader of the demonstration by shooting him point-blank. The United States finds hard to diplomatically defend Israel, yet knows it cannot withdraw its support without risk of destabilizing the Middle East.

Following the advice of Deputy Director of Central Intelligence (DDCI) Jack Ryan, National Security Advisor Dr. Charles Alden enacts a plan to accelerate the peace process by converting Jerusalem into a Vatican-like independent city-state to be administered by a tribunal of Jewish, Muslim, Roman Catholic, and Eastern Orthodox religious leaders, and secured by an independent contingent of the Swiss Guards. As a nod to Israel, the U.S. Army supplies the I.D.F. with more sophisticated equipment and agrees to construct a training base in the Negev Desert run by the U.S. Army's tank warfare specialists and the revived 10th Cavalry Division. To everyone's surprise, Ryan's plan seems to work, in large part due to Ryan's meetings with officials in Israel and Saudi Arabia and the acquiescence of the reformist President Andrey Narmonov in the democratized Soviet Union. With their religious contentions appeased, the factions in the Middle East find it much easier to negotiate their disputes.

White House Foreign Affairs Advisor Elizabeth Elliot holds a grudge against Ryan and Alden and maneuvers against them. She first takes Alden's job as National Security Advisor by using advantage of a sex scandal involving a child fathered by Alden out of wedlock, with the stress contributing to Alden's death in a severe stroke that causes a blowout fracture. She next begins a sexual relationship with widowed U. S. President J. Robert Fowler and manipulates him to publicly omit Ryan's role in the peace settlement, taking credit for himself. After Ryan accuses her of wishing to silence an American opponent of the deal, Elliot engineers a smear campaign accusing Ryan of engaging in an extramarital affair and fathering a child with a young widow. Jack's friends, C.I.A. S.A.D Operatives John Clark and Domingo Chavez, convince Ryan's wife Cathy that the allegations are false. Jack's alleged mistress is Carol Zimmer, widow of Buck Zimmer, who was killed during Ryan and Clark's mission to rescue Chavez and his Army teammates from Colombia in Clancy's preceding novel, Clear and Present Danger. Ryan later decides to retire from the CIA, but not before he puts together a covert operation to uncover corrupt dealings between Japanese and Mexican government officials.

Meanwhile, a small group of Popular Front for the Liberation of Palestine (PFLP) terrorists, enraged at the looming failure of their jihad against Israel, come across the lost Israeli bomb and use it to construct their own weapon by using the bomb's plutonium as fissile material. The terrorists enlist the help of disaffected East German nuclear physicist Manfred Fromm who agrees to the plot to exact revenge for his former communist country's reunification as a capitalist democratic state. With Fromm's expertise, the terrorists enhance the weapon and turn it into a thermonuclear device. The terrorists plan is to detonate the weapon at the Super Bowl in Denver, Colorado while simultaneously staging a false flag attack on U.S. military forces in stationed in Berlin by East Germans disguised as Soviet soldiers. The terrorists are trying to begin a nuclear war between the U.S. and the Soviet Union. The East Germans hope that the war will eliminate both superpowers and punish the Soviets for betraying World Socialism, while the Palestinians hope the attack will destroy the Israeli-Palestinian peace agreement and end U.S. aid to Israel.

Thinking his work is done, the Palestinians kill Fromm. However, Fromm had not yet told them that some of the material he planned to use needed to be purified first. The Palestinians finish the bomb assembly and when it is used, the impure material causes the weapon to fizzle. However, almost everyone at the Super Bowl is killed, including the Secretary of Defense, the Secretary of State, and the commander of NORAD. With the corresponding attacks in Berlin, the United States briefly assumes DEFCON-1 status as Fowler and Elliott prepare for a nuclear war. The crisis is averted by Ryan, who learns of the domestic origin for the bomb's plutonium, gains access to the hot line, and convinces the Soviet President to stand down his country's military.

When the terrorists are captured and interrogated by Clark in Mexico City, they implicate the Iranian ayatollah in the attack. President Fowler orders the Ayatollah's residence in the holy city of Qom to be destroyed by a nuclear strike. Ryan averts the attack by enforcing the two-man rule. The terrorists are delivered to the FBI field office in Buzzard Point, where Ryan questions them. During questioning, Ryan falsely asserts that Qom was destroyed, tricking Qati into revealing that Iran was not involved, and that their deceit was meant to discredit the United States; thus destroying the peace process and allowing the campaign against Israel to continue. Elliot is hospitalized after suffering a nervous breakdown, while Fowler leaves office and is succeeded by his Vice President, Roger Durling (it is implied that Fowler was removed from office through the Twenty-Fifth Amendment to the Constitution, but a later novel clarifies that Fowler resigned in disgrace, while Elliott was forcibly removed).

The terrorists are executed by beheading in Riyadh by the commander of the Saudi Arabian special forces using an ancient sword owned by the Saudi royal family. Later, the sword is presented to Ryan as a gift. In the sequels, the gift (combined with his origins as a Marine) inspires Ryan's Secret Service codename of "Swordsman".

The Sum of All Fears by Tom Clancy is a gripping novel that dives into the world of international espionage and political intrigue. With its intricate plot and well-developed characters, this book keeps readers on the edge of their seats from start to finish. This compelling thriller is a must-read for fans of the genre.