Answer:
The correct answer is that what can limit the Senate in this scenario is the voting process.
Step-by-step explanation:
For the United States be able to meddle and go to war the Senate has to vote two third vote approval after the President send the request.So, if the Senate would not agree with the Presidents notion on a war they can vote to not participare which is what Rand Paul is saying. As well, eventhough Paul is a Republican senator he tend to incline more of a libetarian.