Why are there more bollards being installed in Arlington County?

There has been a proliferation of bollards in Arlington County over the last few weeks.  I know of six that have been installed within one mile of my house, all of which are unnecessary.

From conversations with insiders, I have learned that these bollards are being installed without consensus among staff and against the recommendations of some staff with cycling expertise.  In any case, they are being installed without community input and without any input from the Arlington Bicycle Advisory Committee, of which I am a member.  I have previously posted about how bollards are mostly unnecessary and often create more problems than they solve. (I also provided public comment to the County Board on the morning of May 19.  Text of my comments is here.)

The new East Falls Church bridge went into service last month,
and about a week later four bollards were installed: three at one end and one at the other.  These three went in first:

Then the other one was installed on the other end:

These bollards are senseless.  The intent of bollards is to prevent unauthorized encroachment of motor vehicles on trails.  Since these bollards are not at the intersection of a street and a trail, they do not serve their intended purpose.  It’s not clear what the purpose is, other than to create an impediment and hazard to trail users.