![<> on September 16, 2015 in Simi Valley, California. Republican presidential candidates Donald Trump (L) and Jeb Bush argue during the presidential debates at the Reagan Library on September 16, 2015 in Simi Valley, California.](https://api.time.com/wp-content/uploads/2015/09/donald-trump-jeb-bush1.jpg?quality=85&w=2400)
In the latest round of the never-ending fight between Jeb Bush and Donald Trump, the former Florida Governor penned an op-ed slamming the real estate mogul’s “shocking lack of knowledge” on foreign policy and security issues.
“Let’s be clear: Donald Trump simply doesn’t know what he’s talking about,” Bush wrote in a piece published at National Review. “And his bluster overcompensates for a shocking lack of knowledge on the complex national-security challenges that will confront the next president of the United States.”
Bush outlines specific grievances against Trump, including the time that he said he wished Democratic frontrunner Hillary Clinton had led nuclear negotiations with Iran and the fact that he thinks the United States should not have invaded Afghanistan.
“I am ready to be Commander-in-Chief and lead America during a time of increasing turmoil around the world. Donald Trump has failed to demonstrate the temperament and understanding of our nation’s challenges needed to live up to that responsibility,” Bush writes.
The candidates’ spat can be traced to earlier this month, when Trump seemed to blame George W. Bush, Jeb’s brother, for the terrorist attacks on September 11 that occurred during his presidency. Trump then followed up by saying that he could have prevented the attacks. Bush, meanwhile, called Trump “pathetic” for those comments and criticized him for treating his campaign like reality television.
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Write to Tessa Berenson Rogers at tessa.Rogers@time.com