Do you think we will have a planetary government in our lifetime?

I think we have no choice but to continue how we are. Odd start I know, but here is why. The United Nations is the closest we have to a "planetary government" and there are too many parts to come together to make it effective. The mere savageness of the human race will always triumph any attempt at a civilized working body. The honest truth is that people look out for themselves first. I can not see Iran ever working with Israel. Nor can I see Hezzbollah working with the Israelis. Until the human race does a complete 180 and works for the betterment of all will a planetary government even be able to be considered.

No, there won't be world government. The only reason the EU works is that the European countries share a common culture. Most have roots in the Roman empire, which spanned several nations, and most of the development in european civilization of the last 1000 years has happened through interaction between the states. For instance, the Renaissance staretd in Italy and then spread across Europe. The Englightenment was an Anglo-French thing that spread across Europe. The UK parliament was founded by a visiting Frenchman. Most modern European states are very similar to each other - they are all social democracies with a welfare state. By contrast, the whole world doesn't share a common culture. What might happen is that versions of the EU might spring up elsewhere. For instance the South Americans also have a common culture and have recently signed a traty with a viw to form an EU-like organisation. The South-east asians have already formed a sort of trade group. India, Pakistan, Bangladesh and Sri Lanka have also formed a new group with a view to have a free-trade zone. I think we'll see large continental groupings.

It won't happen without some kind of catastrophic catalyst. Alien Invasion, world wide plague, nuclear holocaust, something like that. We'd have to tear down all our current systems before we could rebuild into a new, better one. And, personally, I don't think any world leaders are humble enough to want to join other nations in a borderless world. If it fails, no one wants to go down in history as the ruler who gave his country away.