There are many answers to this going all the way back to the foundational idea that Rastafari accept His Imperial Majesty as the sole authoritive power over any other. Including President, Royal Family and Pope.
Pope Martin V authorized European crusades into Africa in 1418, and Pope Eugene IV created the Creator Omnium bull which authorized trade of Africans (chattel slavery) so long as they refused to accept Christianity
It gets better...
Pope Alexander VI in 1493 creates the Inter Caetera bull, giving authority of ownership all of the carribean, to King Ferdinand and Queen Isabella.
1622, after more and more Roman Catholic missionaries rise up in Ethiopia. We cant forget the great Emperor Fasilides who expelled them all and dealt with those who refused by penalty of death.
After Menelik II licked down the Italians attempted invasion the first time around, We also can never forget Pope Pius and his backing of the second ItalioEthiopan war attempt. In a famlis speech of August 1935 he described it as a necessary, justifiable or 'just war.'
Video below shows members of the vatican and kissing and blessing the bombs used to attack Ethiopia.
Is that enough?
Burn down Rome