Tantamount:equivalent, as in value, force, effect, or signification.
Dilapidated:to cause or allow (a building, automobile, etc.) to fall into a state of disrepair, as by misuse or neglect.
"The ministry has fallen, Scrimgeour is dead. They are coming."(p. 159)
This quote is significant because it is the line that gets Harry, Ron, and Hermione to start their mission. Rather than putting it off or leaving with a grand exit with many tears and goodbyes, they leave the wedding they are at in a hurry due to this quote, which was a warning by Kingsley.