Yes, they are reprehensible and may be intended to cause terror.  That said, SO FAR, there have been quite a few people who have been assaulted, some with battery, at the hands of Antifa and protesters following the directives of Democratic leaders who claim we can no longer be civil and who instruct their followers to harrass Republican politicians anywhere they see them in public, etc.  The "Resistance" has become a civil war, in some respects.

Trump often acts with little or no restraint and rachets up the political & cultural divide in our nation.  That said, attempts to rationalize bad behavior (or incivility) because someone else did it (or did it first) is either willfully ignoring a large part of the problem we are experiencing today ........... or, imo, are part of the problem itself.

"at the hands of Antifa and protesters following the directives of Democratic leaders who claim we can no longer be civil and who instruct their followers to harrass Republican politicians anywhere they see them in public, etc."  is lacking in substance and factual basis IMO.

A couple of Dems in goverment have taken an extreme position of suggesting people confront their elected officials in public....a position that is disavowed by the vast, vast, vast majority of those on the left with little or no acknowlegdment by those on the right...but none promote violence, and in fact the violence is limited to a small group that I and pretty much all on the left reject and don't connect with.

Your post, and other comments I have read, actually seem to rationalize away these repugnant and sick acts of domestic terrorism by inflating the violence by a small few on the left, and IMO its a pretty hollow attempt at deflection.

I personally don't care who is responsible for these pipe bombs and I just want them captured and punished to the fullest extent of the law.  I don't care if they turn out to be conservative Trump lovers or some derranged and malicious liberal Trump hater.  They don't represent me or my belief system and I am hopeful everyone else feels the same way.