How does one fulfill “not to separate oneself from the community” (al tifrosh min hatzibbur)? Does making aliyah fulfill this obligation?

Without a doubt, the Nation of Israel is halachically, and today and from now on, also religiously, historically and socially in the Land of Israel. Clearly, anyone who wants to be with Am Yisrael should make aliya. In addition, the Rambam (Hil. Tshuva 3, 11) stresses that we must participate and help Am Yisrael in times of trouble, which, for men, surely includes serving in the IDF army, to protect the Jewish Nation and Land from our constant enemies.