The NSA's phone ring tone changes between two takes of the same scene, when the President first gets notified of the attack on the golf course.
A Secretary of State, who is in the line of succession, should not refuse a code indicating a ballistic nuclear attack and waste time telling her DSS agents to find her deputy. Furthermore, she should be immediate relocated to a Continuity of Government site with her family. There also was no mention of COG for the US Legislature or how the other two parts of the triad - bombers and nuclear-capable aircraft - received the disengage code.
The ICBM command center was shown and how the two officers quickly cancelled the launched upon the cancellation order. In reality, the most survivable leg of the nuclear triad, the SSBNs, would have initiated the launch sequence and unable to cancel it.
The storyline shows that the Secretary of State (McChord) and the Director of National Intelligence (DNI) were out of contact when an ICBM launch was detected. The Secretary of State is a regular attendee of the US National Security Council. Even if she was on her day off or leave, she still should be in direct contact. A Diplomatic Security Service agent should not run in an out to inform her what is happening. The DNI is only invited to the NSC when required.
The National Security Advisor (NSA) receives notification of a pending nuclear attack from US Strategic Command. The NSA is not a Cabinet-approved official and not part of the National Command Authority. The Secretary of Defense, who is part of the NCA, should be the individual contacted or the Football carrier who should immediately rush to the President, not told what to do.
Only two United States Air Force officers were shown in the launch center displaying the two-man rule for initiating a nuclear strike, In reality, there's another launch control center where to more officers also turn two keys for the missiles to be launched. A total of four keys are thus required to initiate a launch.
U.S Strategic Command, Sarpy County, Nebraska is Offutt, AFB in Bellevue Nebraska. The AFB shown is actually Altus AFB, in Altus, Oklahoma.
Colonel McPherson tells the President and other NSC members that "London and Alaska already confirmed; Greenland on alert." He should have said "RAF Fylingdales" or just "Fylingdales" which provides ballistic missile warning and monitors launches.
Henry says "I can't crash I'm a trained pilot." However trained the pilot is, a crash can occur due to unexpected mechanical failure or extreme weather.