I was under the impression that the only reason Lukashenko hasn't made his country join Russia yet is that Russia doesn't want Belarus.
Lukashenko has been quietly sabotaging all Union State integration efforts since Putin came to power in 2000. I remember endless talks about installing Russian rouble as Belarusian currency and other such proposals that didn't result in anything fruitful. Some Russian nationalists are mad at him for that.
There were very shaky rumours that when Lukashenko signed the Union State treaty with Yeltsin, he planned to take part in the presidential elections of the unified state. The best friend of the 'international community' Yeltsin was incredibly unpopular among the Russian people (he had an approval rating of only 2% in 1999), and Lukashenko was well known in Russia for his leftist economic policies - liberals condemned him, communists and socialists adored him. It would be very likely for Lukashenko to win the presidential elections with a landslide victory and thus take control of both Belarus
and Russia. Unfortunately for him (and fortunately for the West) some Putin guy became the president of Russia in 2000.
Guys, I need to say that all predictions of Putin's future actions sounded here and elsewhere are extrapolations, and not clever ones, actually - you just assume that Putin is trying to imitate Hitler, and that if Hitler had done something, than Putin will do it too. I can imagine him sitting in his Kremlin office with a checklist, thinking "Hmm, what should I do next? Jews as scapegoat - check, remilitarization - check, Sudetenland - check, Poland - not now... uhmhm... oh, I've almost forgot, Austria! *calls Alexander Grigoryevich* "