There once was a time when candidates joined national campaigns and their opponent would offer them a tepid “Welcome to the fight” greeting.

Not these days.

U.S. Sen. Kamala Harris became former VP Joe Biden’s running mate this week and Donald Trump began a Twitter torrent lambasting the California Democrat for being a weak Democratic primary presidential opponent.

Trump said Harris is the kind of candidate he dreams about. He calls her a champion of the “far left.” Hah! I’ll go instead with some of the progressive outfits who complain that Harris isn’t “far left” enough for them.

In reality, the more I consider Harris’s candidacy, the more I buy into her mainstream moderate approach to governance.

She is a former prosecutor, meaning she hunted down bad guys and put ’em in the slammer. She is no one’s fool. Harris is tough, resilient and vows to work as hard as she can to elect Biden as the next president of the United States.

Harris teamed up once with the late Beau Biden, the former VP’s son, in pursuing fraudulent bankers. Beau Biden happened to be attorney general in Delaware while Harris ran the California justice department.

The old days of common courtesy are gone. Donald Trump is lying in wait (pun kind of intended here, if you get my drift). He is going to cast every possible aspersion he can on Sen. Harris, not to mention what he plans for the former vice president.

Neither of them needs to respond in kind. They have plenty of political action organizations ready to do their own version of the kind of dirty work they can expect from the Donald Trump-Mike Pence team.