Hamas has approximately 40,000 fighter. They proved them self as well-trained, well-organized, highly-motivated, skilled force. During Last Gaza war they had very limited offensive capabilities like grad-rocket, RPG-7, small arms. But now its widely believed that since the Gaza-war Hamas successfully acquired some deadly weapons like long-range fajr-3 & fajr-5 rockets, highly-effective AT-14 kornet anti-tank-missile, AT-5 anti-tank-missile, deadly RPG-29 anti-tank-rocket, SA-18 short-rang man-portable anti-aircraft-missile. May be they have also acquired some anti-ship-missile like noor (c-802), kowser (C-701) and surface-to-surface-missile (SSM) like Fateh-110, zelzal-2 long-range-rocket.
Those new weapons will be very harder to handle for IDF . Now Hamas can attack Tel-Aviv with fajr rockets. Israeli tanks will be venerable with in AT-14 kornet missile and RPG-29’s range like 2006 Lebanon war. So Israeli law makers have to think many times to take decision of a new war against Hamas in Gaza.