Craig makes me crazy sometimes.
He loves to say things that seem axiomatic to him, and treat them as if they were already objectively true. In this video, that something is what he refers to as "God's Nature." And yet, all that Craig can actually know about "God's Nature" is what he has been told by those who taught him his Christian faith, and those who wrote the texts from which that faith derives.
And for the record, reading those texts fully and completely -- every part of them without glossing over any -- will leave even the brightest of us totally confused. The Bible does, for example, make it okay for the Israelites to slaughter male children, but keep female ones (provided they're virgins) alive for their own "use." How, then, can one claim an objective moral evil, coming from God, having to do with taking a female for sexual purposes against her will? Or the murder of children?
But for the record, there is no "objective morality" in the sense that Craig means it. We are, in fact, animals. And yet, all animals have their own nature, and there is such a thing as human nature -- a basic template that describes what it is to be human. Part of that template is that we evolved to be social animals -- dependent for our well-being on others of our kind.
In my view, it is just as easy to construct a morality -- a sense of what is good and evil -- based on the reality of human nature, which is, at its most fundamental, and objective fact. (Exceptions due to errors in gene expression do not count.)