What's really sad is that now you don't have "opponents", you have "enemies".
Ronald Reagan and Tip O'Neill were two men with diametrically opposed beliefs and politics, but they did not hate each other. They were opponents, not enemies. They respected each other and were friendly, though not really the "friends" that some people see in the glow of nostalgia. They both believed in doing the best thing for the country and each knew that's what the other was trying to do too. They just had opposing views of what was best.
That doesn't happen today. People seem to believe that things are a zero-sum game where the only way they can profit is to take from you and the that only way you can profit is to take from them. If they won, then you lost. Nothing is a Win-Win. You must crush your enemy. (And probably drive them before you so you can hear the lamentations of their women.)
When asked about what "enemies" she'd made in her political carrier that she was proud of, one of Hillary's answers was "the Republicans." (The Republicans aren't much better, unfortunately.) Now why on Earth should anyone who considers themself a Republican have any trust in or respect for someone who says that you and they are "enemies"? Even crazy Uncle Joe [Biden] doesn't consider Republicans as "enemies" (though I doubt they're the "friends" he claims they are).