Much grousing about the expense of President Obama's India trip. This is silly and vindictive. The one thing this country owes its leader is to spare no expense in protecting him. Especially when his first stop is Mumbai, scene of one of the most savage and sustained terror attacks in modern times.

It is protested that Britain's prime minister took a British Air flight when he traveled here in July. So what? To be blunt about it: A once-imperial middle power flies commercial; America flies colossal. Why do you think we built that 747 flying palace emblazoned with the presidential insignia - if not to land to awestruck crowds wherever it goes?

There was grumbling about the White House taking over every room at Mumbai's five-star Taj Mahal Palace hotel. What is the Secret Service to do? Allow suites to be let to, say, groups of Pakistani madrassa instructors?

I will admit that Indian authorities went somewhat overboard when they cut down the coconuts surrounding the Gandhi museum in Mumbai. I am no expert on this, having never been subject to a coconut attack, but it seems to me that a freefalling coconut is no match for an armored car built to withstand anything short of a small nuclear device. Now perhaps the enemy, always racing one step ahead of us, is working on the dreaded RPC - the rocket-propelled coconut. I'm not privy to all the intelligence here, and, try as I may, I could get nothing out of the Coconut Desk at CIA. Nonetheless, to this outsider, the anti-coconut measures seemed a bit excessive.

But I digress. The only alternative to drawing down the Treasury to move the president around safely is for him not to go at all. And that's not an alternative. Presidential visits are the highest form of diplomacy, and the symbolism alone carries enormous weight. No one remembers what Nixon did in China; what changed the world is that Nixon went to China.

The India visit was particularly necessary in light of Obama's bumbling overenthusiasm in his 2009 trip to China in which he lavished much time, energy and praise upon his hosts and then oddly tried to elevate Beijing to a G-2 partnership, a kind of two-nation world condominium. Worse, however, was Obama suggesting a Chinese role in South Asia - an affront to India's autonomy and regional dominance, and a signal of U.S. acquiescence to Chinese hegemony.

This hegemony is the growing source of tension in Asia today. Modern China is the Germany of a century ago - a rising, expanding, have-not power seeking its place in the sun. The story of the first half of the 20th century was Europe's attempt to manage Germany's rise. We know how that turned out. The story of the next half-century will be how Asia accommodates and/or contains China's expansion.

Nor is this some far-off concern. China's aggressive territorial claims on resource-rich waters claimed by Vietnam, Brunei, Malaysia, the Philippines and Japan are already roiling the neighborhood. Traditionally, Japan has been the major regional counterbalance. But an aging, shrinking Japan can no longer sustain that role. Symbolic of the dramatic shift in power balance between once-poor China and once-dominant Japan was the resolution of their recent maritime crisis. Japan had detained a Chinese captain in a territorial-waters dispute. China imposed a rare-earth mineral embargo. Japan capitulated.

That makes the traditional U.S. role as offshore balancer all the more important. China's neighbors from South Korea all the way around to India are in need of U.S. support of their own efforts at resisting Chinese dominion.

And of all these countries, India, which has fought a border war with China, is the most natural anchor for such a U.S. partnership. It's not just our inherent affinities - being democratic, English-speaking, free-market and dedicated to the rule of law. It is also the coincidence of our strategic imperatives: We both face the common threat of radical Islam and the more long-term challenge of a rising China.

Which is why Obama's dramatic call for India to be elevated to permanent membership on the U.N. Security Council was so important. However useless and obsolete the United Nations, a Security Council seat carries totemic significance. It elevates India, while helping bind it to us as our most strategic and organic Third World ally.

China is no enemy, but it remains troublingly adversarial. Which is why India must be the center of our Asian diplomacy. And why Obama's trip - coconuts and all - was worth every penny.

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