Succeeded in science. In medicine. In technology. In space exploration. In ability to respond to crises. In ability to relatively quickly detect and correct mistakes in political decisions.
Nothing changed since 1930s in Germany... are you sure about that?
As opposed to vast success under Mao? If you measure success in millions of dead from hunger, then yes.
Why would you want to maximize political stability? Hitler, Franco, North Korea were/are very politically stable: no real elections, no meaningful methods to effect change (a.k.a. "instability").
Your point is?
How is this relevant to the fact that current president was elected in a free and fair (i.e. Western style) elections?
You seem to be a typical Western leftie.
Typical Western leftie lived all his/her life in the West. Therefore he/she doesn't notice how many things work well in the West society. Just like you don't realize how precious is the ability to breathe air - until you are deprived of such ability (say, if you are drowning). So, a lot of things in the West work very well, but it is "natural" and he/she doesn't notice it.
However, West is not ideal and there are numerous things which can be improved, such as: financial mafia, businesses which tries to cut corners on safety and pollution, dishonest politicians who push policies beneficial for them and their friends but harmful for the country, etc, etc, etc.
Which makes you to come to conclusion that West is a horrible society.
I, on the other hand, had a "privilege" to live not only in the Western society, but also to live in "socialist paradise" of Ukraine (former part of USSR) before that. I know that supermarkets full of goods, mobile phones, computer in every house, freedom to say "our president is a f*cking idiot, let's elect someone less moronic" are not naturally happening things!
I think my perspective is much wider than one of people who only lived in a Western country (and no, tourist visits to non-Western countries don't count).
My opinion is that Western society is better than any other society currently existing, or existed in the past, on this planet. Note: "better" is not the same as "good" or "the best thing possible". The history of mankind is far from over. We will most likely devise an even more efficient societal constructs.