James McCulloch most likely supported the idea that Congress could create banks because

D. He didn't want to pay state taxes on his bank.

Before McCullock vs Maryland, banks in the state had a law requiring federal banks to pay state taxes. The Supreme Court ruled in favor of James McCulloch, giving Congress the power to create a federal bank. James McCullock supported the idea that Congress could create banks because he did not favor paying state taxes on his own bank.