Instead of "left" versus "right," think of two different core competences.
The Democratic Party is basically a governing party, organized around developing and implementing public policies. The Republican Party has become an attack party, organized around developing and implementing political vitriol. Democrats legislate. Republicans fulminate.
In theory, politics requires both capacities — to govern, but also to fight to attain and retain power. The dysfunction today is that Republicans can't govern and Democrats can't fight.
Donald Trump is the culmination of a half century of GOP belligerence. Richard Nixon's "dirty tricks" were followed by Republican operative Lee Atwater's smear tactics, Newt Gingrich's take-no-prisoners reign as House speaker, the "Swift-boating" of John Kerry, and the GOP's increasingly blatant uses of racism and xenophobia to build an overwhelmingly white, rural base.
Atwater, trained in the southern swamp of the modern Republican Party, once noted: "Republicans in the South could not win elections by talking about issues. You had to make the case that the other guy, the other candidate, is a bad guy." Over time, the GOP's core competence came to be vilification.
The stars of today's Republican Party, in addition to Trump, are all pugilists: Mitch McConnell, Lindsay Graham, Ted Cruz, and Marco Rubio; Florida governor Ron DeSantis and Georgia's Brian Kemp; Fox News's Sean Hannity and Tucker Carlson; and attack dogs like Rudolph Giuliani and Roger Stone.
But Republicans don't have a clue how to govern. They're hopeless at developing and implementing public policies or managing government. They can't even agree on basics like how to respond to the pandemic or what to replace Obamacare with.
Meanwhile, the central competence of the Democratic Party is running government — designing policies and managing the system. Once in office, Democrats spend countless hours cobbling together legislative and regulatory initiatives. They overflow with economic and policy advisers, programs, plans, and goals.
But Democrats are lousy at bare knuckles political fighting. Their campaigns proffer policies but are often devoid of passion. (Hillary Clinton's 2016 presidential bid was little more than a long list of detailed proposals.) Democrats seem stunned when their GOP opponents pillory them with lies, rage, and ad hominem attacks.
This has put Democrats at a competitive disadvantage. Political campaigns might once have been about party platforms, but today's electorate is angrier and more cynical. Policy ideas rarely make headlines; conflict does. Social media favor explosive revelations, including bald lies. No one remembers Hillary Clinton's policy ideas from 2016; they only remember Trump's attacks on her emails.
As a result, the party that's mainly good at attacking has been winning elections — and pushed into governing, which it's bad at. In 2016, the GOP won the presidency, along with control over both chambers of Congress and most governorships. On the other hand, the party that's mainly good a governing has been losing elections — pushed into the role of opposition and attack, which it's bad at. (House speaker Nancy Pelosi, however, seems to have a natural gift for it.)
This dysfunction has become particularly obvious — and deadly — in the current national emergency. Trump and Senate Republicans have let the pandemic and economic downturn become catastrophes. They have no capacity to develop and implement strategies for dealing with them. Their knee-jerk response is to attack — China, Democrats, public health officials, protesters, "lazy" people who won't work.
Democrats know what to do — House Democrats passed a comprehensive coronavirus bill in May, and several Democratic governors have been enormously effective — but they've lacked power to put a national strategy into effect.
All this may change in a few months when Americans have an opportunity to replace the party that's bad at governing with the one that's good at it. After all, Joe Biden has been at it for most of the past half century.
Trump and the GOP will pull out all the stops, of course. They've already started mindless, smarmy attacks.
The big question hovering over the election is whether Democrats can summon enough fight to win against the predictable barrage. Biden's choice of running mate, Kamala Harris, bodes well in this regard. Quite apart from all her other attributes, she's a fierce fighter.