The correct answer to this open question is the following.
There is no question, just a quote. Although the question is missing we can say that the question should be "What was the event that forced President Reagan to make this address?
The correct answer is the Iran-Contra Affair.
US President Ronald Reagan was being interviewed in a major tv news show when he acknowledged some of the mistakes in the Iran-Contra Affair. He admitted that he had no excuses, there had been mistakes. This opinion made his popularity soar again to 51%.
The Iran-Contra Affair started in August 1985 and ended in March 1987. This political scandal involved Senio officials of the Reagan administration who sold weapons to Iraq, in order to support the Contras in Central America, specifically, in Nicaragua.