After his recent marijuana arrest, legendary musician Willie Nelson said it was time for an increased political focus on changing our nation's failed marijuana laws. "Tax it, regulate it and legalize it," he said, "and stop the border wars over drugs. Why should the drug lords make all the money? Thousands of lives will be saved." With that in mind, MPP has teamed up with the folks at Change.org to ask Willie to help the cause in a way that only he can: [I]f Nelson wants to help end pot prohibition,…