Today's Headlines and Commentary

On Sunday, the U.S. Customs and Border Protection Agency shut down the border crossing in both directions at Tijuana and fired tear gas at migrants who tried to evade a Mexican police blockade and get to a border crossing that leads to San Diego, reports the Times.

Russia-Ukraine tensions escalated as Moscow opened fire on three Ukrainian ships near the Kerch Strait, a key water route; in response, the Ukrainian parliament approved President Petro Poroshenko’s proposal to impose martial law in the country for a period of 30 days, reports the Washington Post.

Syria called on the United Nations to condemn rebel forces in the wake of another apparent chemical attack in Aleppo that affected more than 100 people, says the Times. No deaths have been reported, and the origins of the attack and substance used are unclear.

Taiwanese President Tsai Ing-wen resigned as head of Taiwan’s governing Democratic Progressive Party after it suffered local election losses to the Kuomintang party, which supports closer relations with China, reports the Times.

Dozens of U.S.-backed fighters were killed by Islamic State in a battle in Deir Ezzour province in Syria this weekend, reports the Wall Street Journal. U.S. airstrikes helped end the fight.

France and Germany joined forces on a broader European effort to circumvent U.S. sanctions on Iran by agreeing to host a payment channel that would operate on a system of credits rather than direct payment transfers, thus avoiding U.S. sanctions, reports the Journal. The U.S. has worked to deter countries from hosting the channel.

ICYMI: Yesterday on Lawfare

Jen Patja Howell posted an episode of the Lawfare Podcast in which Benjamin Wittes sat down with John Carlin to discuss Carlin’s new book with Garrett Graff, “Dawn of the Code War: America's Battle Against Russia, China, and the Rising Global Cyber Threat.”

Dafna H. Rand argued that the U.S.’s Yemen policy must change, and relevant lessons can be applied to similar “related war” efforts.

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