The capitol is (normally) a public building. There is a sitting senator who has been arrested at a protest in the building. Likewise it was not long ago that th

The capitol is (normally) a public building. There is a sitting senator who has been arrested at a protest in the building. Likewise it was not long ago that the capitol was full of protesters accosting senators in the lead up the the supreme court pick. It's not meant to be a secure building that takes an army to get into.