Abraham Lincoln had great clarity of mind and expression, and he worked to make it clearer -reading Euclid in his early 30s to train his mind.

After I published a book called Lincoln's Virtues a wit said that my next book should be Lincoln's Vices. But in my opinion that would be a short book!

The situation Abraham Lincoln faced was unique. In his view, the United States was threatened with destruction, ruin, overthrow, perishing - all words that he used - which is not the case for any other president, including the current one - Barack Obama.

The US did not have any big supply of good generals in Civil War, and some it did have went with the rebels. If Robert E.Lee had stayed with his country the story would have been different.

Yes, the rise in corporate power had roots in the gearing up for the Civil War. Abraham Lincoln was a Whig, a supporter of government aid to expanding industry - to internal improvements that supported the growth of business. He was an early capitalist, not one who wanted to preserve some rural paradise.

There was specific constitutional provision for emergency measures in the case that Abraham Lincoln faced - an insurrection - which no other president has faced.

Abraham Lincoln had a deep realism he did not deceive or mislead himself, but faced the world he had to deal with as it really is. At the same time, he had a striking moral intelligence, and a confidence in the working of his own mind and conscience.

All presidents - particularly war presidents, presidents inclined to the imperial presidency - invoke Abraham Lincoln as a justification, but they omit these three defenses of Lincoln's strong actions. Suspend habeas, blockade, increase army without congress, arrest Maryland legislators, etc.

I do not think you can fault Abraham Lincoln for picking generals that did not work out, because, as he said to John Hay when he went back to George B. McClellan in the fall of 62, we have to work with what we have.

Abraham Lincoln did not contend that his actions were immune from Congressional correction on the contrary, he specifically said he was acting beyond the present provisions in the expectation that congress would retroactively approve, which they did. He did not say anything like Richard Nixon: if the president does it is legal.

Abraham Lincoln was not philosopher, exactly. But he did have a strong mind, which sought generalizations as well as particulars. He had a terrific memory.