I get that folks are feeling hopeless right now. It's an understandable response to seeing two mass shootings in under 24 hours.
On climate change things are shifting politically, fairly quickly. Younger conservatives are prioritizing climate change as an issue because there is no doubting the science, and the under-40 crew whose futures *will* be wrecked by this stuff is taking notice. It's greed still, but similar to the struggle against Fascism in the 1940s, it will take all of us, including the otherwise bad and self-interested, to overcome this challenge. It's only older conservatives who really hold things back in that regard, people who have nothing to lose from climate change and gains to be made in the rest of their days for continuing to deny it.
The gun control conversation has shifted since Parkland. The NRA now is the weakest it's been for a while, and is quickly becoming toxic whereas before they were seen as just another civil society organization (like how NRA used to partner with all kinds of mainline businesses for member discounts, the kinds of member discounts you'd get for being a Girl Scout, etc), people of conscience no longer want to associate with the NRA and that's impacted their bottom line.
Politically the pro-gun crowd is on the march in red states, but movement is being made elsewhere, like red-flag laws that allow court orders to seize guns temporarily from people judged to be a threat to themselves or others, such as a personal mental health crisis or a domestic dispute. Meanwhile gun ownership as a percentage of households in the country is at the lowest recorded per the 2014 General Social Survey (haven't looked at it since). It's a dying culture lashing out.
The reason you see bad people lash out more and more is that they see the writing on the wall. Diet racists who used to live in comfortable bubbles of privilege now have those bubbles popped and become belligerent. Gun nuts seek to intimidate by force. Plutocrats seek to plunder what they can before the hammer drops on climate change policy.
Things can get better, and the conditions to make that possible are happening now, but they need effort.
If you want the earth to have a future:
https://www.sunrisemovement.org/
If you want to stop gun violence:
http://lawcenter.giffords.org
If you care about exposing white terrorism:
http://splcenter.org
