I'm familiar with a fair number of those books. All of the authors that I have read and heard speak are in fact, not motivated by objective scientific goals but instead by a need to justify their version of fundamentalist religion.
We could probably have an interesting discussion on whether progress in science depends upon objective motivations or not, but it is patently obvious that the writers in your list are interested in these topics because they think that mainstream evolutionary biology and geology disprove their incredibly narrow version of religion. Phillip Johnson took up these topics because he had a born again religious experience and Henry Morris holds to the most absurd ideas of numerology which he expounds in an appendix to one of his books.
It's probably worth noting that a Muslim fundamentalists are picking up ideas from US Christian creationists and passing them along to Middle Eastern Muslims.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
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