Scholars differ as to the principles and techniques of crisis management. However, most agree that negotiation mediation, nonmilitary pressure, non-violent military maneuvers, and violence are five major components of crisis management technique. For President Bush, the Iraqi invasion of Kuwait constituted a challenge to U. S. national interests in the post-Cold War era. Bush used at least three options to defuse the crisis. After economic sanctions had failed to compell President Saddam Hussein to yield, a U.N. resolution was obtained that empowered the U.S. to use all necessary means to expel Iraqi troops from Kuwait. The diplomatic approach was adopted only after U.N. security Council Resolution 678 was available to Washington. The Baker-Aziz talks in Geneva turned out to be futile because neither side would put itself in the shoes of the other. Saddam's underestimation of the Americans' will to fight was a critical factor of Desert Storm. The 100-hour land war demonstrated President Bush's restraint in not expanding his goal to the overthrow of Saddam Hussein. However, there has been controversy over whether President Bush stopped the war too early. The second U.S. Military strike against Iraq in January 1993 to a certain extent proved that Bush had not wholly solved the problems that caused the Persian Gulf Crisis in 1990.