[nine_k]

The problem with socialism without free market is that it has been tried many times, and it drastically lowers productivity, leading to deficits. People start spending their copious free time in lines waiting for the rare and insufficient goods to arrive. If you think USSR was long ago and this time it will be different, look at Venezuela.

[etplayer]

This was not a problem with Socialism, it was a problem with the form of economic planning used. We must also bear in mind that there are forms such as market Socialism. Neither the USSR nor Venezuela paid attention to cybernetic planning; scientists in the USSR were repeatedly shut down by bureaucrats for suggesting it.

There exist modern planning methods, though still academic, such as those elaborated by Cockshott and Cottrell in Towards a New Socialism, it's worth a look if you haven't seen it already.

Nobody is suggesting rigid five year plans any more.