  The 2HDM possesses a neutral scalar interaction eigenstate whose tree-level
properties coincide with the Standard Model (SM) Higgs boson. In light of the
LHC Higgs data which suggests that the observed Higgs boson is SM-like, it
follows that the mixing of the SM Higgs interaction eigenstate with the other
neutral scalar interaction eigenstates of the 2HDM should be suppressed,
corresponding to the so-called Higgs alignment limit. The exact Higgs alignment
limit can arise naturally due to a global symmetry of the scalar potential. If
this symmetry is softly broken, then the Higgs alignment limit becomes
approximate (although still potentially consistent with the current LHC Higgs
data). In this paper, we obtain the approximate Higgs alignment suggested by
the LHC Higgs data as a consequence of a softly broken global symmetry of the
Higgs Lagrangian. However, this can only be accomplished if the Yukawa sector
of the theory is extended. We propose an extended 2HDM with vector-like top
quark partners, where explicit mass terms in the top sector provide the source
of the soft symmetry breaking of a generalized CP symmetry. In this way, we can
realize approximate Higgs alignment without a significant fine-tuning of the
model parameters. We then explore the implications of the current LHC bounds on
vector-like top quark partners for the success of our proposed scenario.
