Bill Moyer did a nice episode showing the disproportionate number of report Wapo did in pushing fro a war in Iraq [1].
Among notable neoconservatives/neoliberals working at the post and using it as a pulpit are Robert Kagan [2] who worked on the "Project for the New American Century" that became the blueprint of Iraq war agenda.
For me the nail in the coffin against the Post was when they used an unknown research firm to push for a neo-mccarthyism Russian connection to over 200 blogs and publishers [4],[5].
[0] https://en.wikipedia.org/wiki/Fred_Hiatt
[1] http://www.pbs.org/moyers/journal/btw/citations.html
[2] https://en.wikipedia.org/wiki/Robert_Kagan
[3] https://en.wikipedia.org/wiki/Project_for_the_New_American_C...
[4] https://www.washingtonpost.com/business/economy/russian-prop...
[5] https://theintercept.com/2016/11/26/washington-post-disgrace...