The Nazi Holocaust destroyed most of the traditionally religious Jewish population of Eastern Europe, and the subsequent establishment of the State of Israel appeared to make the Orthodox opposition to Zionism an anachronistic relic.
Nevertheless, following the war the remnants of Lithuanian Jewry made every effort to rebuild their religious institutions and society, especially in Israel and in America, where new communities were established built around traditional Yeshivot of the sort that had flourished previously in Lithuania.
Unlike the situation in Europe, where the yeshivot had been integrally connected to and supported by their host communities, the post-war institutions were usually insular, cut off from prevailing social trends. This led to imposing more demanding standards of halakhic interpretation, since the study did not have to respond to a real social context, and membership in the community was restricted to those who had chosen to accept its standards.
The revived communities were able to benefit from the generosity of the modern "welfare state," and a larger proportion of the young men were able to remain in kolels, advanced academies for married students. The State of Israel was also tolerant in allowing exemptions from military service to full-time yeshivah students, a policy born from a combination of respect for the victims of the Holocaust, and a conviction that religious Judaism was merely a holdover from the past that would probably die out within a generation of two.
The revived Lithuanian Orthodoxy has maintained a surprising vitality, facilitated by the decline of secular ideologies and a much larger birth-rate among its membership.
In Israel the Lithuanian yeshivah world remained affiliated with the Aguddat Israel movement, a coalition of Orthodox groups whose attitudes towards the Jewish state ranged from pragmatically supportive to utterly hostile.
In the 1980's the Lithuanian faction, under the spiritual and ideological leadership of the outspoken head of the Ponevich Yeshivah in B'nai Brak, Rabbi Eliezer Shach, split off to become a separate Political Party (Degel Hattorah The Banner of the Torah), devoted to the promotion of its own interests (especially its schools) and its traditional hostility to the secular Zionist leadership.
Sources: Prof. Eliezer Siegel's Home Page