I have questions concerning the sentence "But the war isn’t being sold on these grounds.":
What does the sentence mean?
How are the word combinations "isn’t being sold" and "on these grounds" used in the sentence and how are they generally used?
Where does the pronoun "these" refer to?
The context is the following:
Despite these dangers, there is a case for attacking isis. Part of it is humanitarian: Millions of people now live in a caliphate in which many women cannot leave their homes unless accompanied by a man, and religious minorities can be sold as slaves. Allowing isis to expand, and potentially threaten Jordan or Saudi Arabia, would produce misery on an epic scale, intensify the refugee crisis already roiling Europe, and destroy America’s reputation as the underwriter of Middle Eastern order.
But the war isn’t being sold on these grounds. The presidential candidates are not telling Americans that a greater short-term terrorist threat is the price they must pay to liberate oppressed Arabs, protect friendly regimes, and prevent a greater danger down the road. Instead, candidates are promising, at least implicitly, that if America intensifies its war, the terrorist threat will decrease.
The source is Why Attacking ISIS Won't Make Americans Safer where you can find even larger context if it is needed.
I have made my own research and I have my own suspicions what it could mean, but its meaning is still unclear for me. The most I want is an explanation in this specific case, but providing a clear, general reference links are also more than welcome.