Here’s my diagnosis. If partisan warfare–that is, politicians place their power of their party ahead of solving the country’s problems–then Americans must vote these politicians–i.e., congresspersons–out of office–and replace them with congresspersons that will, on important matters at least, put solving the country’s problems ahead of their party’s political power. Essentially, this entails a willingness to cut deals with the other party–accepting certain policies of the other side, while getting policies one really values in return. This is the way our system works–and it won’t work unless politicians are willing to do this. I’m not suggesting that congresspersons have to do this on every issue (although I would be happy if they did), but they need to do this enough times, especially on critical issues, to make the system work. If they almost never do this, they’re unfit for office in my opinion, and voters should sent them packing, even if they align with a voter’s political ideology. This is how to address the gridlock and dysfunction–vote out the congresspersons that prevent the political system from functioning.
By the way, in my view, who voters elect as president will have little impact on this problem. The power of the POTUS is limited in addressing the problem I describe above. I don’t think the situation will get better until voters politically punish congresspersons that almost never compromise and make deals, while also politically rewarding the congresspersons that do.