Democratic frontrunner Hillary Clinton rebuked defended and Republicans Nato in a counterterrorism address after fatal strikes in Brussels.
Her remarks contrasted with her Republican counterparts, specifically Donald Trump, that has proposed scaling back US commitments.
Mrs Clinton said the US and Arab partners should consult intensely and stand with Europe.
America must not turn its back she said during remarks at Stanford University in California, and dissing them isn’t an effective way to resist terrorism.
Mr Trump’s calls to reinstate using torture and water boarding to glean advice from those were addressed by her.
The fatal strikes in Brussels that killed more than 30 individuals will be the “latest savage reminder” that more must be one to get the better of to so called Islamic State (IS) militant group, she said.
Mrs Clinton also said proposition in Congress to create a national commission could help fight online radicalisation.