“He attacks me every day. He attacks me every day with barbarities,” Bush said in Spanish in response to questions from reporters at a Presbyterian school here. “They’re not true. What we did today was to put out in his words to show that he’s not conservative.”

But in fully embracing a fight against Trump, Bush is embarking on a risky strategy that could further fuel Trump’s unexpected rise and complicate his own path to the nomination. Allies of the former Florida governor insist that he had no choice but to adopt a more aggressive posture, elevating his feud with Trump to the marquee contest in the GOP primary contest…

“Knowing Jeb, I’m sure he’d prefer to be talking about policy proposals rather than trading verbal jabs with Trump,” said Ana Navarro, a longtime GOP strategist backing Bush. “But what . . . is he going do? Let the guy mischaracterize his record and positions and attack him daily? Enough is enough. If Trump wants to pick a fight with Jeb, Jeb needs to embrace it and hit back.”…

“We have reached a moment where conservatism isn’t defined by issues anymore for a big percentage of the country,” said Steve Schmidt, a senior adviser to Sen. John McCain (R-Ariz.) in the 2008 presidential campaign.