Historically, the alliance’s command structure and military capabilities were developed to ensure effective deterrence of the former Soviet Union and the European states feared that its involvement in the Middle East would have negative consequences for security in Europe. This led to the development of flexible mechanisms in the post-Cold War era that support so-called out-of-area operations relying on European structures, “coalitions of the willing”, and cooperation with partner countries. Yet, the European countries’ efforts were scattered, and were often overlooked by the US, leading to greater pressure on NATO involvement. The NMI, on the contrary, is a full-bodied mission appearing in the Middle East for the first time. It duplicated the model of the Resolute Support Mission in Afghanistan. Thus, NMI also may lead to a more even distribution of security-related costs between the European members of the alliance and the US. This is indeed an important consideration for Trump. The NMI means more support from the US’ allies to stabilize the situation in the Middle East (which, Trump has pointed out, impacts Europe’s security too.)
MK Bhadrakumar, 'US takes Israel’s advice for unified ‘Syraq’ strategy', Asia Times