"He's been indoctrinated with LIES, thinking he can override his own INCOMPETENCE. He's as nervous as you can get!" Mr. Trump wrote on Truth Social.
Mr. Walz appeared nervous at the beginning of his debate against Sen. J.D. Vance of Ohio, giving halting answers in which he twice confused Israel and Iran.
On his first question, Mr. Walz confused Israel with Iran.
"Iran -- er -- Israel's ability to defend itself is absolutely fundamental," he said in an answer punctuated with "uh" pauses.
He later said countering "the expansion of Israel and its proxies is an absolute fundamental necessity for the United States to have the steady leadership there," clearly mixing up Israel and Iran at the beginning of the thought.