If he is not good for U.S. allies or for the U.S.'s foreign policy position, he will certainly not do much good for the U.S. They go together. Grinding an axe against foreign countries he doesn't like should not come before the national welfare.
U.S. warns governments, bankers Iran sanctions still in place (Reuters)
from the article: Obama nominates Chuck Hagel as next U.S. secretary of defense