Japan must be doing something well... I don't know if passport ranking is included in any human development index, but somehow being able to negotiate diplomatically with large numbers of "others" is evidence for an advanced society (and in some ways a role model if we ever want to reach some sort of pax humana)
Being rich, highly educated, low in criminality, low in illegal emigration means that other nations are more willing to welcome you in. Think of who you would welcome into your own home and they map pretty homomorphically to the same set of rules you would set at the national level i.e. probably someone who won't steal your things, is good company, won't break your rules, or overstay their welcome.
Not diplomacy or government action, it simply helps if you are the sort of nation whose travelling supporters volunteer to help clean up their mess in stadiums after their matches in international tournaments. Contrast that with away supporters of other nations (looking at you England :D)
