Watching "Legend Quest" on the Syfy channel, because I'm procrastinating (read learning how to repoint masonry for a home project). They're on a Grail Quest.
What pure, unmitigated crap. Seriously, I know sixth graders who could deconstruct your theory, dude. Let me see, so you think that the St. Clair family, priors of Roslyn Chapel, allowed the Pilgrims to sail to the new world with the Grail. At a time when ships coming over the N. Atlantic didn't have a good safety record (let alone the leaky ships the King of England gave the Pilgrims), do you really think the "keepers of the Grail" would take a chance of having it go to the bottom of the Atlantic? Or that colony settlements at the time had a 50/50 chance of survival.
Ha, ha, ha ha ha. Um, yeah. And no, that's not a chalice on top of the monument, that's an urn with a flame on top. Chalices don't have flames, but urns, in funerary iconography do.
We'll ignore the whole "Providence is where America was founded" bullshit you're pushing. Because, obviously, you have no grasp of history.
Serious fail. Aliens crashing at Roswell seems almost reasonable given the cuisinart blending of myth and conspiracy theory you're doing there.