washington democrats push gun curb late mass shoot unite state co-opting republican mantra build public support defang opposition time get tough national security shore national security long pillar republican orthodoxy staunch opposition gun control massacre 49 people orlando florida last sunday deadly mass shoot modern u.s. history gunman pledge loyalty islamist militants may leave republicans shaky grind national security drive debate democrats see powerful argument simply advocate need curb gun violence country 320 million 310 million weapons although orlando gunman omar mateen believe help extremist islamist group target gay nightclub investigate u.s. authorities possible link terrorism subsequently clear prompt democrats clamor legislation expand background check prevent people u.s. terrorism watch list buy gun vote four measure schedule monday u.s. senate two sponsor democrats two republicans many republicans democrats oppose strict gun curb partly constitutional ground every senator go say whether terrorists get gun terrorists get gun democrat senator chuck schumer tell reporters thursday terrorists need fear streets aleppo mosul fallujah streets unite state gun unless pass tough laws add senator ed markey massachusetts democrat president barack obama democratic presidential candidate hillary clinton homeland security secretary jeh johnson take tack week gun measure safeguard terrorism republicans long criticize obama tough enough national security fight islamic state orlando massacre san bernardino california shoot december couple inspire islamic state capture attention american public way previous mass shoot say tom diaz former member national rifle association gun right lobby back gun control change dynamic whole issue say diaz author expert terrorism gun industry shift sentiment hearten families 20 elementary school children six staff members kill newtown connecticut 2012 champion last big ultimately unsuccessful push gun control 71 percent americans include eight 10 democrats nearly six 10 republicans favor least moderate regulations restrictions gun accord reuters/ipsos poll conduct monday thursday 60 percent late 2013 late 2014. diaz believe republicans must look care keep gun hand so-called homegrown extremists balance issue due process constitution second amendment right bear arm form backbone nra opposition gun control republicans say new laws necessarily keep weapons hand people intent harm keen avoid twin two issue gun control issue u.s. senator ted cruz say thursday terrorism issue republican strategist ron bonjean say democrats must careful overplay hand rhetoric could sound like government overreach americans believe second amendment even current efforts fail new push national security may prove democrats best shoot eventually lure republican support issue flounder decades chance democrats talk tough term safety security also link gun issue say robert spitzer political science professor state university new york cortland.some notable republicans appear will week engage debate gun control party presumptive presidential nominee donald trump vow meet nra talk ways bar people certain government watch list buy gun top republican senate majority leader mitch mcconnell say open suggestions experts prevent terrorism suspect acquire firearms call orlando shoot calculate act terror unclear whether trump mcconnell would throw weight behind measure acceptable democrats democratic u.s. representative jim himes say hold great hope gun legislation would advance reason see compromise anytime soon congress actually act wake orlando would tacit admission side gun something happen orlando oppose isis say use acronym islamic state democrats new line gun control national security