Exclusive: DHS Secretary Markwayne Mullin Says Canada Not Taking Border Security SeriouslyU.S. Department of Homeland Security Secretary Markwayne Mullin said the success of the Trump administration's policies at the southern border is now putting pressure on other areas and identified issues at our northern border with Canada. The post Exclusive: DHS Secretary Markwayne Mullin Says Canada Not Taking Border Security Seriously appeared first…Breitbart News Network11d agoWhole story →SecurityJusticenorthern border security concerns