MACS(SW),
No, the two-party system isn't killing us. It's the two-party system that gives the USA its political strength and stability. Our winner-take-all system gives the winning party a definite term in office to implement their plan, whatever it may be. At the end of the term the party asks for another term. If they were successful then the people will likely give them another term. If not, the people will turn the old guard out and elect someone else.
In a parlaimentary or proportional representation system the winning party is only one no-confidence vote away from losing power and the ability to implement their program.
One look at the Italy or Israel should be enough to scare anybody away from a parliamentary system.
In Italy there have been so many governments since WWII that I've lost count. I think its been 40, but I'm not sure. Imagine 40 federal elections in the USA over the past 60 years. NO THANKS!
In the case of Israel the problem isn't no-confidence votes, but the multitude of factions. In order to form a government the largest party must try to include enough factions to have a majority. Again, try to imagine the USA and the number of parties that would spring up. The country would disintegrate because there would not be a clear majority. NO THANKS!
I know the system we have isn't perfect, but its better than the alternatives.
Sorry for the rant but I appreciate you listening.