The US State Department issued a travel restriction on Wednesday to its citizens, restricting them to travel to North Korea. In addition to restricting travel to Korea, US citizens in the North Korean territory will have until September 1 to leave the country.

The Korea's People Army participating in an annual military parade in Pyongyang
As any other rule, there are exceptions. American journalists and humanitarian workers who are or will need to enter North Korea will not be affected by the measure. Regardless the exceptions, North Korea has become the forbidden land for Americans as the only destination in the world where the citizens of Uncle Sam’s land will be prevented from traveling.
In June, the American student Otto Warmbier died after receiving a 15-year sentence from the North Korean government. He was released from his sentence after diplomatic pressure from the United States, but he was already in a coma. It is not yet known why or how the student would have fallen ill during his time in prison, but speculators believe the student was the target of several practices of torture. North Korea denied any accusation of torture days after the speculations hit the news.
Through its state-owned TV, North Korea reported that Warmbier's death was “a mystery” and rejected charges that he had entered a coma because of torture and assaults in prison.
The measure was announced in order to avoid that other cases such as the students.
Regardless of how Otto died, our thoughts and prayers are with the Warmbiers and the rest of
Americans worldwide.