Combatting Terrorism in Tunisia Emergency Support Act of 2017 This bill declares that it is the policy of the United States to assist the government of Tunisia in eliminating terrorist organizations that operate in Tunisia and neighboring Libya and preventing fighters in Syria from returning to Tunisia. This bill expresses the sense of the Congress that: significant reform that protects fundamental human rights is necessary to enable the Tunisian security services to combat terrorism and reinforce the rule of law; expeditious consideration of sales, leases, grants, or transfers of defense articles, services, and equipment is consistent with U.S. policy to assist in eliminating terrorist organizations that threaten Tunisia's national security; Tunisia's peaceful pursuit of democracy should be fully supported by the United States; organizations such as Ansar al-Sharia and the Islamic State have created terrorist sanctuaries in Libya and represent a significant threat to Tunisia's democratic government; and supporting Tunisia's orderly reform of its economic and social sectors should be a U.S. priority. The bill authorizes the Department of State to: provide assistance to strengthen and reform Tunisia's security sector; support Tunisia's efforts to combat terrorism; provide assistance to support Tunisia's democracy and civil society; provide assistance to support Tunisia's border security by enhancing its capabilities to interdict illicit weapons trafficking; reprogram certain funds to support Tunisia's economic reforms; and enter into a memorandum of understanding with Tunisia to increase military cooperation, including joint military exercises, personnel exchanges, and enhanced strategic dialogue. The President is authorized to provide defense articles, services, and training to Tunisia to counter terrorist threats. The State Department shall submit a strategic plan within 90 days to carry out this bill.