Time will tell, but I believe that honor goes to "Ted Cruz for President".
With Ted making his the face of Conservatism and himself its true standard personified, not to mention all other candidates in comparison being simple posers at best or charlatans at worse, "Ted Cruz for President" is what is "destroying" Conservatism.
Conservatism isn't a cult of personality, especially not a cult built around someone as flawed as Canadian-born Ted Cruz.
It's the same old, same old once again this election season, but hopefully we'll get it out of our system early and can get beyond it.
People always will disappoint, but principles and the Father from Whom those principles flow will never disappoint.
Unfortunately for his cultists, Ted Cruz is just a lawyer with a billable integrity and theirs is now tainted by their willful association.
The last thing Ted Cruz is is a cult of personality.