While Donald Trump successfully employed a "divide and conquer" strategy in the Republican presidential primary, general elections -- and politics overall -- are about addition more than subtraction. And for Trump the path to the presidency is just not adding up yet.

For months, Trump and his aides have promised that once the primary was over, the GOP's presumptive nominee would appear more disciplined and "presidential." But in the days since his final Republican opponents dropped out of the race, Trump has been the same old Trump.

Trump has changed his basic policy positions, like taxes on the wealthy and the minimum wage. He still engages in distracting Twitter wars with people who are not his opponents. And he cannot shake blasting US Senator Lindsey Graham (something that is so July 2015).