Trump's strategy of smearing and badmouthing is actually very strategic:

[DetlefK]

http://nymag.com/daily/intelligencer/2016/12/the-conspiracy-on-behalf-of-conspiracy-theorist-donald-trump.html

While it may give Trump too much credit to assume he has followed a considered strategy, there is a coherent pattern to the discourse he has promoted. It is a comprehensive attack on empiricism. He spreads distrust against every institution, so that the only possible grounds for belief is trust in a person. The suspicion he spreads against every institution protects Trump from accountability. If everybody is guilty — what governments don’t murder journalists? — then nobody is guilty. Questions about Trump’s own suspicious financial and political ties are simply more conspiracy theories.

[guillaumeb]

1. Recommended. And Trump follows the standard GOP technique here.

A GOP that promotes an anti-science agenda,
a GOP that promotes an anti-IRS agenda,
a GOP that promotes a generalized distrust of all government action,
a GOP that invented the "liberal media" meme because the media insisted on exposing the crimes and lies of Richard Nixon.