ARTICLE I, SECTION 8:
“The Congress shall have power...To make rules for the government and the regulation of the land and naval forces”
“.To make rules for the government and the regulation of the land and naval forces””
Maybe “regulation of land and naval forces” refers to (a) how they are organized (what are the military departments), (b) how major appointments meet the requirement for Senate approval, (c) conduct of military personnel including things like the UCMJ, (d) organizations of the military schools, and similar matters, but maybe does not refer to foreign policy that may cause the POTUS to detail out some use of the military?????
While other sections of Article 1 Section 8 provide for Congressional authority to “raise armies” that does not seem to provide powers to “direct” those armies.
What the Constitution does provide to Congress regarding the military and Congress’ check on the executive in that regard, specifically in Article 1 Section 8, and generally, is the power of the purse.