Good catch! I'd forgotten about that. Say, they had a pretty good 797 year run going there!
Washington DC was sacked by the British in 1814. Somehow I don' tthink we'll beat the Roman's 797 year record, that would mean we make it to 2612 without someone taking Washington.
There are days I wonder if we'll make it 7 months!
At this point, Washington is more likely to be sacked by the citizenry than any invader. =)