Of course these days Buddhists project their 21st century obsessions onto Buddhism and call it engaged-Buddhism, but Buddha wasn’t silent on politics. He said that monks and serious mediators should not get involved in politics  and only talk of the Dharma or keep silent . Elsewhere Buddha outlined that one should not even get involved in talk of worldly things ranging from politics to food .
Buddha says among the conversations one should avoid are about “kings, robbers, & ministers of state; armies, alarms, & battles; food & drink; clothing, furniture, garlands, & scents; relatives; vehicles; villages, towns, cities, the countryside; women & heroes; the gossip of the street & the well; tales of the dead; tales of diversity, the creation of the world & of the sea; talk of whether things exist or not.” 
In fact, what Buddha said monks and serious mediators should talk about is “modesty, contentment, seclusion, non-entanglement, arousing persistence, virtue, concentration, discernment, release, and the knowledge & vision of release .” He told us,
“not [to] submit to figments. Do not follow views and have no association with knowledge and knowing common-place opinions. Rather be indifferent to them(saying) ‘Let others take them up” .
 A Fistful of Sand by Ajaan Suwat Suvaco
[2} SN 21.1
[3} AN 10.69