You can hill the enemy and frustrate him as well.
Take the enemy's strength him by stealing away his money

Fight for the enemy's supply wagons.
Capture his supplies by using overwhelming force.
Reward the first who captures them.
Then change their banners and flags.
Mix them in with you won wagons to increase your supply line
Keep your forces strong by providing for them.
This is what it means to beat the enemy while you grow more powerful.

Again this reminds me of the stuff in Iraq. Could they used the captured guns to provide for the Iraq military? Could they reuse explosives? The iraq military could be supplied for decades with what saddam left behind.