Trump need to be very careful with the arms of Rick, but tomorrow the militants. Today they can be friendly to America, but tomorrow, circumstances may change and they turn their weapons against the Americans.
The Kurds can be trusted. They are fighting against militant Islam for the last many decades. They are essentially a secular fighting force. If the Islamist FSA can receive weapons from the US, then I don't see a reason why the Kurds shouldn't have them.