Final answer:
The phase in which troops were built up in Saudi Arabia during the Persian Gulf War was called Operation Desert Shield. Saddam Hussein launched Scud missiles at Israel to draw them into the conflict and gain support of Arab nations.
Step-by-step explanation:
The phase in which the U.S. and its allies built up troops in Saudi Arabia (August 2, 1990-January 17, 1991) was called Operation Desert Shield. This phase was the initial response to the invasion of Kuwait by Iraq. It aimed to deter further aggression and protect Saudi Arabia from potential Iraqi attacks.
During the Persian Gulf War, Saddam launched Scud missiles at Israel in an attempt to draw them into the conflict and to gain support of Arab nations. This move highlighted the volatile situation in the region and the potential for the conflict to escalate.
Learn more about Operation Desert Shield, Scud missiles, Persian Gulf War