I interpret the first of your questions in terms of the previous sentence: '"Dance for the crowd" is the new order, with newsmen leading the politicians like bears on the leash'. The writer thinks that newsmen, particularly radio commentators, just say whatever pleases the audience, and use politicians for their entertainment value. If a politician had 'real convictions' then they would not be willing to acquiesce to such demands.
'without a moment's pause for gathering wisdom' sounds archaic to my ear. People would normally say, 'speak without thinking' or 'without stopping to think'. In other words, to say whatever comes first into their head, even if that is superficial and not well thought out.
'The talkers are rising above the thinkers', people just say anything that comes into their heads, and thus wisdom, and profound thought, is lost. The writer is railing against the inanity of the popular media.