The US was determined to prevent foreign countries from giving the Confederacy official recognition and support because they believed it would have significant geopolitical implications. If foreign powers had acknowledged the Confederacy as a legitimate government, it would have been a major blow to the US's sovereignty and territorial integrity. It could have also emboldened the Confederacy and prolonged the war, making it more difficult for the US to restore the Union. Additionally, foreign recognition and support for the Confederacy could have led to greater international involvement in the conflict, potentially drawing in other countries and increasing the risk of a wider war.