North Korea has been lobbing missiles in the direction of Japan, as a deliberate act of provocation and bravado.
Commentators on television can't mention this fact without at once saying "Japan is the country's former colonial overlord." And so it is, but I don't think the pertinent history has anything to do with the choice of missile-test target, or whatever 'this' is.
Just so no one will say I ignored it, though, let's say a few words about that history, even though we're just taking this stuff from wikipedia.
Korea was never colonized by one of the usual suspects, one of the western European powers one thinks of when the subject comes up.
The Russo-Japanese War was fought at the start of the 20th century largely over the issue of in whose sphere of influence did Korea fall. The Japanese won.
Not long thereafter, in 1910, the Japanese forced on the Koreans a Treaty of Annexation. This begins the period referenced when the news talking heads speak of Japan as the former colonial power.
The war that tore apart Europe and much of the Middle East in 1914-18 had muted echoes in Korea, but by the time it was over, Korea had a liberation movement. Japanese troops apparently killed thousands of demonstrators in Seoul on one especially busy day, March 1, 1919.
Though the leaders of the independence movement had been in part inspired by Wilson's 14 points, the US didn't stand with them when the crunch came. In April '19 the US ambassador in Tokyo received instructions from the State Department that the Seoul consulate "should be extremely careful not to encourage any belief that the United States will assist the Korean nationalists in carrying out their plans and that it should not do anything which may cause Japanese authorities to suspect American government sympathizes with the Korean nationalist movement."
That's enough work for my typing fingers today.
Tomorrow I'll speak to my skepticism as to why any of this has much to do with the NK missile tests in 2016.