It was helped along in 2014 by the release of a United Nations Commission of Inquiry report that highlighted the problem, particularly the system of labor camps.
"Through most of the long history of the global community's engagement with North Korea, the horrific human rights abuses committed by the regime have been known but not necessarily been central to how we have engaged", said a senior Obama administration official.
In recent years, the North Korean authorities have been repeatedly accused of human rights violations.
There are precedents for the USA putting heads of state on the Treasury blacklist. "Additionally, transactions by US persons involving the designated persons are generally prohibited".
The US report states that "The Ministry of People's Security operates a network of police stations and interrogation detention centers, including labor camps, throughout North Korea" where " during interrogations, suspects are systematically degraded, intimidated, and tortured". Apart from that, according to the North Korean government spokesman, Washington must guarantee that it will not deploy offensive nuclear weapons in South Korea and neighboring countries and will not use them against North Korea.
Another North Korean official linked to the abuses is the Minister of People's Security Choe Pu Il.
North Korea at that time warned it could reduce US military installations in the Pacific to ashes, and said, "Let's turn Seoul and Washington into a sea of fire".
A USA senior official said Kim is "rather plainly ultimately responsible for the actions of his regime including his repressive policies".
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South Korea on Thursday welcomed the move by the USA, saying it hoped the move would shine a light on human rights "violations" in the North.
In response, the United States urged the North to "refrain from actions and rhetoric that further raise tensions in the region" and said it will continue to work for improvement in the North's human rights situation.
Five entities and 10 other individuals are also named in this latest round of sanctions.
Policymakers often worry that targeting a country's leader will destroy any lingering chance of rapprochement, former diplomats say.
"What the US did this time, not content with malignantly slandering the Democratic People's Republic of Korea, is the worst crime that can never be pardoned", North Korea's foreign ministry said, according to KCNA.
"... The US dared challenge the dignity of (North Korea) supreme leadership, an act reminiscent of a new-born puppy knowing no fear of a tiger", the statement said.
Harrell added that it was unlikely that any assets would be blocked "given the realities of where Kim Jong Un and his cronies likely hide their assets". He predicted an "epic" reaction from Pyongyang, with "numerous official and state media denunciations".