So. As the Roman Empire got too large and complex they went to a Eastern/Western Empire situation. If you take as given that the job in front of today’s US executive is too complex to be handled by one man, would instead of a geographical a similar separation of responsibilities might help allow someone with who could be more expert in the area and a smaller contingent of responsibilities make sense? For the following take it as a given (as in we won’t argue that point) the job needs to be broken up and concentrate instead on how to do so.
This question it seems has two parts. The first is, wow to best break the job up. Foreign/domestic seems an obvious choice, but there may be other ways. Bertrand de Jouvenel suggested in his political philosophy that there were two types of leadership, one that drives forward toward a goal and one that can reconcile differences between people. Perhaps that would be another way to divide the two. Any other suggestions?
The second part is, how to implement this? Could this be done by dogmatic precedent (like the two term limit which followed Washington’s example for so long)? Could a President announce at his inauguration that he was doing this, and his vice President was going to, say, handle 100% of foreign affair issues and he would 100% concentrate on the domestic affairs. The titular President would promise to rubber stamp any decisions made by his VP as if he were signing them as long as there were in the foreign affairs sphere and vice versa. Would this fly? If not, why no? Or would a full Constitutional amendment process be required to effect this?