President Joe Biden will block the purchase of US Steel by Nippon Steel, as the US administration concluded that the $14.9 billion transaction poses an insurmountable national security risk. This move is in line with the stance taken by Kamala Harris, the Democratic presidential candidate, in her recent campaign in Pennsylvania. Harris emphasized that the American steel manufacturer "should remain American.

The decision of the White House follows the recommendation of the Committee on Foreign Investment in the United States (Cfius), which rejected the deal on national security grounds. This development comes in an already politically charged atmosphere, as both Harris and the Republican candidate Donald Trump support the decision.

The steel manufacturer US Steel warned that thousands of jobs in Pennsylvania are at risk if the deal fails. The company also feared that it would have to address serious questions about the future of its headquarters in Pittsburgh.

The shareholders of US Steel had approved the deal earlier in the year, although it is now under review by both the Justice Department and Cfius. This reflects the complex and often controversial aspects of international acquisitions, which can touch upon significant national interests.

This case underscores the political risks associated with high-profile assets and demonstrates how political pressure can fundamentally alter the outcomes of such international agreements. It remains to be seen how this decision will impact the political landscape in the U.S. and relations with key allies like Japan in the long term.