“Border arrests peaked at more than 144,000 in May, an influx that prompted Trump to threaten Mexico with crippling tariffs unless the government of president Andrés Manuel López Obrador took immediate steps to curb the flow. Mexico responded by deploying thousands of national guard troops to ramp up arrests and intercept more Central American families heading north.” WaPo: Trump officials say border crossings fell again in August, heap praise on immigration enforcement deal with Mexico.