Story highlights Clinton used a 30-minute speech at Stanford University to outline how she would try to defeat ISIS

Reince Priebus, chairman of the Republican National Committee, blasted Clinton's address

Palo Alto, California (CNN) Hillary Clinton sharply criticized the foreign policy proposals of Republican presidential front-runner Donald Trump and competitor Ted Cruz on Wednesday, arguing that the world would be more dangerous should they win the White House.

Clinton used a 30-minute speech at Stanford University to outline how she, as president, would try to defeat ISIS and protect the United States against terrorism. The former secretary of state, pulling at length from her four years as America's top diplomat, urged tighter cooperation with allies while also pushing those countries to do more to combat terror.

While aides maintained that the address was purely focused on policy -- "It's not a politics speech," said one -- much of Clinton's remarks were framed by Trump, a real estate mogul, and Texas Sen. Cruz. The speech gave Clinton an opportunity to cast Republicans as a risky bet on foreign policy.

"If Mr. Trump gets his way, it will be like Christmas in the Kremlin," she told experts and students at the prestigious university a day after terror attacks in Brussels killed more than 30 people.

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