The lack of engagement with israel is a result of the distancing themselves from Judaism. A generation ago liberal jews were connected at treat by nostalgia. Today they lack that. Of course there is a core of activists. They do not reflect the broader trend of assimilation that is the true reason behind the lack of involvement of te non orthodox.
Judge orders Jerusalem Gay Pride attacker to undergo psychiatric evaluation (Haaretz)
from the article: Orthodox Jews dominate joyous Israel Parade in New York