In Israel, the IDF is responsible for external defense but also has some domestic security responsibilities; its primary operational focuses include the threat posed by Iran, instability in Syria, and terrorist organizations, including HAMAS, Hizballah, the Islamic State of Iraq and ash-Sham (ISIS), and Palestine Islamic Jihad (PIJ)

since its creation from armed Jewish militias during the First Arab-Israeli War in 1948-49, the IDF, particularly the Ground Force, has been guided by a requirement to rapidly mobilize and defend the country’s territory from numerically superior neighboring countries; the active-duty military is backed up by a large force of trained reserves--approximately 300-400,000 personnel--that can be mobilized rapidly 

Israel’s primary security partner is the US; consistent with a 10-year (2019-2028) Memorandum of Understanding, the US annually provides over $3 billion in military financing and cooperative military programs, such as missile defense; the US also provides Israel access to US-produced military weapons systems including advanced fighter aircraft; Israel has Major Non-NATO Ally status with the US, a designation under US law that provides foreign partners with certain benefits in the areas of defense trade and security cooperation

the United Nations Disengagement Observer Force (UNDOF) has operated in the Golan between Israel and Syria since 1974 to monitor the ceasefire following the 1973 Arab-Israeli War and supervise the areas of separation between the two countries; UNDOF consists of about 1,000 military personnel (2024)