Stocks were under assault on multiple fronts in a busy end to the week. Geopolitical threats rose overnight after the U.S. military executed an airstrike against Syria in retaliation to a chemical attack earlier this week. Closer to home, the March jobs number was a big miss as late-season snow snarled weather-sensitive industries. Defense stocks saw some of this biggest gains of the day. Boeing (BA - Get Report) , Lockheed Martin  (LMT - Get Report) and Raytheon (RTN - Get Report) , the maker of the Tomahawk missiles used in the attack on Syria, each moved higher. Twitter  (TWTR - Get Report) was under pressure after defying a U.S. government request for records that could identify anti-Trump users. The social network is challenging that order in court, arguing that attempts to unmask users violates the First Amendment. PriceSmart  (PSMT - Get Report) fell after quarterly earnings and sales missed estimates. Overall revenue climbed 2%, while net warehouse club sales grew 1.8%.

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