World War I: the real underlying cause

According to AFP, a picture acquired from the historical archives of Sarajevo shows Archduke Franz Ferdinand exiting a train upon his arrival in Ilidza, western suburbs of Sarajevo, on June 27, 1914, the day before his assassination. The assassination of Archduke Franz Ferdinand by 19-year-old Bosnian-Serb nationalist Gavrilo Princip in Sarjevo, 100 years ago this June, 28, is widely considered to have sparked the World War I. No doubt, that picture carried by Business Recorder in its Sunday's issue says it all.
"It was on a Sarajevo street corner on June 28, 1914, that the 10-year-old Bosnian-Serb nationalist short dead the archduke and his wife with a Browning revolver, setting off a chain of events that sucked Europe's great powers into four years of unprecedented violence that redrew the world map," according to a news report carried by the newspaper. But one must not lose sight of the fact that a resurgence of imperialism or a period of colonial imperialism was the real underlying cause behind the Great War; and the assassination of the heir to the throne of Austria-Hungry triggered the war, setting off a diplomatic crisis.