Public opinion polls consistently show that the majority of Americans support stricter gun control measures, along with all of the other policies included in the Justice Democrats platform. Given that this is the case, I highly doubt that their position of gun control will stop them from succeeding.
Also, I don’t buy the idea that simply flipping to the other side when it comes to gun-related issues will suddenly lead to some huge surge in support for the Democrats. The Democrats are already being accused of being too conservative by the left — moving to the right on guns will only exacerbate those complaints, and potentially lead to even larger chunk of their base leaving to join the Green Party or perhaps register as independent.
I speak for myself and many others when I say that I won’t be supporting any Democratic candidates that “take up the cause of gun rights”. I’ll support candidates that are content with keeping gun laws as they are and won’t impose any new measures, but anyone actively claiming to loosen current restrictions will not get my support.
I also disagree with your assessment that a full implementation of the Justice Democrats platform will amount to a loss of our “basic rights”. If anything should be considered be a basic right, it’s not gun ownership, but rather healthcare and education (which are both included in the Justice Democrats platform). Second of all, there is no person or entity in mainstream politics promising to completely erode gun rights. Not Justice Democrats, not the Green Party, no one.
Getting rid of your “basic rights” would be banning guns, not simply imposing stricter restrictions on them. There’s a major difference between the two.
It should also be noted that Kyle Kulinski (one of the co-founders of Justice Democrats) stated in an interview that they allow a little wiggle room when it comes to their platform. He said that there two policies Justice Democrats are required to support, but that they’re open to taking in candidates with different views and positions on other policies. Unfortunately, I can’t remember exactly what the two required policies, but I know for a fact that gun control wasn’t one of them.