WASHINGTON, Dec 5 - The United States will reassert itself in the Western Hemisphere, build military strength in the Indo-Pacific, and possibly reassess its relationship with Europe, President Donald Trump said on Friday in a sweeping strategy document that seeks to reframe the country's role in the world.

The National Security Strategy, released overnight, described Trump's vision as one of "flexible realism" and argued that the U.S. should revive the 19th century Monroe Doctrine, which declared the Western Hemisphere to be Washington's zone of influence. It also warned that Europe faces "civilizational erasure" and must change course.

The document is the latest - and clearest - expression of Trump's desire to shake up the post World War Two order led by the United States and built on a network of alliances and multilateral groups.

"President Trump's foreign policy is pragmatic without being 'pragmatist,' realistic without being 'realist,' principled without being "idealistic," muscular without being 'hawkish,' and restrained without being 'dovish,'" the 29-page document says.

"It is motivated above all by what works for America."

The paper, which is released by every new administration and guides the work of many government agencies, said Trump would "restore American preeminence" in the Western Hemisphere.

"This 'Trump Corollary' to the Monroe Doctrine is a common-sense and potent restoration of American power and priorities, consistent with American security interests," the document says, suggesting that the large U.S. military build-up in the region is not temporary.

Since taking office in January, critics have said Trump's rhetoric evokes modern-day imperialism in the Western Hemisphere. He spoke early on, in vague terms, of retaking the Panama Canal and annexing Greenland and Canada.

More recently, the growing U.S. military presence in the Caribbean and threats of land strikes in Venezuela and in other countries where drug cartels operate have added to regional concerns.

The United...