Presidential response

Shortly after the incident, President Clinton criticized radio talk show hosts. "They spread hate. They leave the impression that, by their very words, violence is acceptable." Clinton did not mention anyone by name, but later singled out the radio host G. Gordon Liddy (who had told his listeners to shoot federal ATF officers, who had illegally entered their homes, in the head rather than the chest because they wear bullet proof vests).

Schools across the country were dismissed early and ordered closed in the wake of the bombing. The fact that 19 of the victims had been children, most of them in the building's day care center, was seized upon by the national media. A photograph of firefighter Chris Fields removing infant Baylee Almon (who later died in a nearby hospital) from the rubble was reprinted worldwide and soon became a symbol of the tragedy. The photo, taken by utility company employee Charles H. Porter IV, earned the 1996 Pulitzer Prize for Spot News Photography.

In addition to the children with a direct connection to the bombing, others became distressed after hearing media reports and later research established that many showed symptoms of post-traumatic stress disorder (see references).

In the first two days after the bombing, President Clinton and his wife, Hillary, were very concerned about how children were reacting to the bombing. They asked aides to talk to child care experts about what to tell them about the bombing. On the Saturday after the bombing, April 22, the Clintons gathered children of employees of federal agencies that had offices in the Murrah Building in the Oval Office and answered their questions.

The remains of the half-destroyed Federal building were demolished in May 1995. Some legislation was also introduced in response to the attack, notably the Antiterrorism and Effective Death Penalty Act of 1996. Until the September 11, 2001 attacks, the Oklahoma City bombing was the worst act of terrorism within U.S. borders, but not the worst against the United States (the worst act of terrorism against the U.S. before the Oklahoma City bombing was Pan Am Flight 103). The site became part of the National Park Service. On February 19, 2001 an Oklahoma City bombing museum was dedicated at the Oklahoma City National Memorial Center.

"In the largest criminal case in U.S. history, FBI agents conducted 28,000 interviews and collected 3.5 tons of evidence and almost 1 billion pieces of information in the Oklahoma City bombing case."

Michael Fortier, an accomplice and key informant, was sentenced to 12 years in prison and fined $200,000 on May 27, 1998 for failing to warn authorities about the attack. He was released for good behavior on January 20, 2006.

Timothy McVeigh was sentenced to death for the bombing after being convicted of, among other things, murdering federal law enforcement officials. He was executed by lethal injection at a U.S. penitentiary in Terre Haute, Indiana, on June 11, 2001. An accomplice, Terry Nichols, was sentenced to life in prison after being convicted of manslaughter in a federal court trial. Nichols stood trial in McAlester, Oklahoma, on state murder charges starting on March 1, 2004 and was convicted of 160 counts of first-degree murder plus other felony charges on May 26. The penalty phase of the state trial, in which he could have been given the death penalty, ended in a jury deadlock. He was sentenced to 160 consecutive life-without-parole sentences by the Presiding Judge Steven W. Taylor.

In many ways the Oklahoma City bombing spelled the end of the anti-government militia movement to which McVeigh was linked. In the years following the bombing most such groups either disbanded or were pushed farther to the fringes of American politics. Additionally, by being the first major American city to suffer a mass-casualty terrorist attack, Oklahoma City's response to the bombing was carefully scrutinized by security experts and law enforcement in the years following the bombing, and then again following the September 11, 2001 attacks.

In the weeks immediately after the Oklahoma City bombing the federal government surrounded federal buildings in all major cities with prefabricated Jersey barriers to ward off similar attacks. Most of these temporary barriers have since been replaced with permanent security barriers which look more attractive and are driven deep into the ground (so that they are more sturdy). All new federal buildings must furthermore be constructed with truck-resistant barriers and with deep setbacks from surrounding streets to minimize their vulnerability to truck bombs.

In February, 2004 the federal government reopened their investigation into the bombing after FBI agents investigating the MidWest Bank Robbers (a white supremacist gang McVeigh had associated with prior to the bombing) discovered blasting caps of the same type used in the Oklahoma City bombing. Later in 2004, at the Terry Nichols state bombing trial, Judge Taylor found there to be no credible, relevant, or legally admissible evidence of any persons other than McVeigh and Nichols having directly participated in the bombing of the Murrah federal building.

In 2004, a new federal campus (designed with a special focus on security) opened in Oklahoma City, a block from the site of the bombing.

According to Mark Potok, the director of Intelligence Project at the Southern Poverty Law Center, law enforcement officials authorities have foiled 60 domestic terror plots since the Oklahoma City bombing. They were prevented due to measures established by the local and federal government to increase security of high-priority targets and following up on hate groups located within the United States.

In 2006, congressman Dana Rohrabacher said that the Subcommittee on Oversight and Investigations of the U.S. House Committee on International Relations, which he chairs, would investigate whether the Oklahoma City bombers had assistance from foreign sources.