There are arguments to be made in both directions on this issue. The Constitution gave the president the power to be the commander-in-chief of the military. However, it also gave Congress the power to make rules to regulate the military, to declare war, and to set the levels at which the military will be funded.
Many people would argue that the president should have more control over the military. The main reason for this is that the president is one person and Congress is made up of a very large number of people. This means that the president can make quick decisions that are needed for military purposes while Congress could not. Imagine, for example, Congress trying to make the decision to go into Pakistan and attack Bin Laden’s compound.
On the other hand, we can argue that Congress should have more control over the big picture of military actions. In other words, Congress should have more power over things like whether we will deploy troops to Afghanistan or Iraq. The reason for this is that Congress is the most representative body. It is more democratic to have all of our representatives have a say on what our military does than it is to allow one person to make these decisions.
Therefore, we can argue that Congress should have more power over the "big picture" without trying to make the day-to-day tactical decisions.