Mate, you originally asserted that no country in the Middle East is allowed to develop weapons and I corrected you on this count. Now you have shifted the goalpost but I shall remind you that Saudi Arabia has lRBM class ballistic missiles.
www.armscontrol.org
The US and Israel are very close but the US also value bilateral relations with other countries in the Middle East and will allow them to field a capable force. US-led forces fought a war with Iraq to protect Saudi Arabia and liberate Kuwait in 1991. The US also helped Saudi Arabia blunt attacks of Houthi during Saudi-Yemen War by providing advanced equipment to Saudi forces and share valuable intel with them.
Turkey is also developing its weapons. The US does not mind.
The US does not necessarily agree with an ally on all counts but continue to honor its commitments to multiple countries around the world. This might surprise you but the US and Israel also have tensions and disagreements. Google is your friend.
American foreign policy is complex in reality but the US draws a line at proliferation of nuclear weapons.