Charles Spurgeon Commentary 2 Chronicles 12:4

"And he took the fortified cities which pertained to Judah, and came unto Jerusalem." — 2 Chronicles 12:4 (ASV)

And he took the fenced cities which pertained to Judah, and came to Jerusalem.

When God intends to chasten a people, He does not take long to do it, nor can their weakened strength successfully oppose their enemy.