So the REAL question is what WILL stop it. Saying that "This one is a bad person and did nothing to change it" doesn't work. Saying "The previous one did nothing to change it" doesn't work.
Voting for "The other party" doesn't work.
No, I do not have the answer, because if I did I would be giving it.
What must be done to change the status-quo with minimal violence or bloodshed is to unite people under common values, such as the massive & ongoing civil rights violations/infringements that most people agree are wrong, regardless of what political stripe they self-identify as.
Likewise, the militarization of domestic police forces and their gradual shift from a community law enforcement role to more resemble a national occupation force complete with armored vehicles and heavy crew-served weapons.
Start focusing on what we have in common, not what divides us. Despite what those with power would like you to believe, we have much more in common than we have differences. Those commonalities are also those of a much more fundamental and essential nature than our differences.
Extremely few on any side of the political spectrum in the US (barring government & MIC) wants an Orwellian surveillance//security/police state.
I'd have no problem at all standing side by side in public protests and demonstrations with almost anyone from TEA Party member to PETA and/or LGBT activist and beyond who also was willing to postpone our arguments for our common interests in a free and open society without mass domestic surveillance & data analysis and a militarized police force performing military-occupation and wealth-confiscation roles more than any sort of community-based & controlled "officer of the peace" roles.
Look, people, yes we have beefs over stuff *BUT*, unless we unite and curb government power and size, it won't matter because very soon none of us will have any choices about anything nor any meaningful rights at all.