When a candidate has won the Presidency, they have 3 months before taking office. During this time, they should have national security briefings. Until that time, none of the candidates for president should receive breifings.
Serious concerns exist, within the citizenry, that certain candidates could cause the nation and our troops harm if they mishandle the secrets of the United States.
In fairness, we should no longer extend national security briefings to any candidate.