Insiders claimed the 20-year-old would-be assassin of Donald Trump was on an alleged “suicide mission” and wanted to “trigger a second U.S. civil war”, RadarOnline.com can reveal. Thomas Matthew Crooks, 20, of Bethel Park, Pennsylvania, came within mere millimeters of achieving his goal when he opened fire at the Trump rally, killing one attendee and nearly missing the ex-president’s head. Amid criticism of the Secret Service security detail – including initial red flags that were ignored, like Crooks entering the venue with a rangefinder and video footage of the shooter lurking beyond the sec…