The criticism Boehner is receiving is entirely self-inflicted. He had an opportunity to make a statement on behalf of his party about national unity in the face of unspeakable violence, and he punted. Clearly he should have known how that would look: petty and disrespectful. And that’s regardless of the extenuating circumstances.
Could it be that he was actually afraid of committing the House GOP to standing with the President, lest he get blowback from his political base?