The notoriously jingoistic Sun , which has never before shown even a hint of friendship toward Japan, published an editorial promising a new era of better relations between our two countries.
The Sun promised a better relationship with Japan in an editorial they published. 
mnli hypothesis: The Sun promised a better relationship with Japan in an editorial they published.  premise: The notoriously jingoistic Sun , which has never before shown even a hint of friendship toward Japan, published an editorial promising a new era of better relations between our two countries.