Attacks from the air on IS forces are necessary but insufficient. Because IS is a territorially based entity, there must be a ground dimension if the effort is to progress; after all, only ground forces can take and hold territory.
叙利亚问题要棘手得多，因为这里仍在内战，并且各外部势力正在争夺影响力。对伊斯兰国力量的空中打击是必要但不充分条件。由于伊斯兰国是一个基于领土的实体，因此，要想取得进展，必须派遣地面部队；毕竟只有地面部队能够夺取并守卫领土。