Real Genius/YMMV


 * Did Not Do the Research: The scriptwriters, when they set the plot point that 'the only use of this weapon is to assassinate unsuspecting targets from space'. In fact, the exact same qualities that they listed for why there was allegedly no non-murder use of the dynamite laser (extremely high power but narrow beam focus and limited firing time) were what the Strategic Defense Initiative project was publicly known to be pursuing at the time of filming re: building a laser weapon that could actually kill Soviet ICBMs as they were launched. And while that's still a military application its a defensive one, not an assassination one.
 * Additionally, the plot point of 'this weapon could secretly kill people from space'. There is nothing secret about giant heat spikes from orbit, because that's exactly what every superpower on the Earth has entire networks of satellite detection equipment constantly searching for. Sudden unexplained thermal blooms in that large a magnitude are the chief indicator of ICBM launch, so every strategic defense network on the planet watches the entire observable surface of the Earth for those 24-7-365.
 * Nowadays DARPA is working on even more non-covert-assassination applications for military lasers (high spikes of power, little or no sustained burn), such as air-defense artillery and anti-vehicle support weapons.
 * Esoteric Happy Ending: Hathaway's weapon worked. Blowing up Hathaway's house still proved that it worked; and it's shown that the CIA knew it was a problem with targeting; not the laser function. Chris had given the schematics (the dynamite laser) to Hathaway before he decided against it. Even if the original Kill Sat was destroyed after destroying Hathaway's house due to the reflected laser; Hathaway and his military contacts would have made copies of this information.
 * That is, unless it was subject to added public and Congressional scrutiny--see Headscratchers.
 * There is a reason that they spent actual screen time showing the efforts Chris and Mitch went through to decoy the Congressman and Dr. Meredith out to where they could actually see the laser firing, and that was to communicate to the audience 'the secret black project is no longer secret - both Congress and the academic community are now fully aware it exists'.
 * Ho Yay: Between Chris and Mitch, so very much.
 * Straw Man Has a Point: At no point does any of the protagonists bother to exposit why it's so wrong to build a laser capable of vaporizing ground targets from space. They simply state that it is, and act on that basis.
 * Hathaway lied to them and used them to build what would be called a "weapon of mass destruction". It was their tech and work and he stole it from them to use to kill people. They had a moral connection to that work and could not stand the idea of their work used to kill people, like how Nobel hated how his "mining device" was used to kill people and so used the profits to work towards peace.
 * That's apocryphal. Nobel started his career as an explosives and ordnance engineer, his first patent was for improved methods of manufacturing gunpowder, and his family's business was in munitions and weapons manufacturing. He only changed his philosophical tack later in life, but there was no point at which his work was 'stolen' from him for use in killing people. His original career was military R&D -- he was consciously choosing to work on building methods of killing people.
 * While having moral objections to the work, they apparently have no moral objections to still wanting the course credit and promised perks of doing the work. Profiting off of building a weapon is apparently fine as long as the weapon doesn't actually get used.
 * Hathaway lying to them is a perfectly justifiable reason for them to be angry at Hathaway. Being scammed for free labor is a perfectly justifiable reason to want to be paid some kind of fair value in return for their contribution. But neither issue has anything to do with why the laser, itself, is supposedly such a bad thing to have exist.
 * The Woobie: Mitch, deliberately.