Can we still rely on USA to protect us in the region?

I refer to the current show of force by USA in the South China Sea:

US bombers' flyover 'serious military provocation', says China
More:
https://www.malaysiakini.com/news/323970

The long drawn spat among China, Vietnam, Philippines and Malaysia over Spratly Islands has again drawn the attention of Big Brother, the United States of America.

China has taken the initiative of reclaiming land, resulting in a man-made island large enough to act as a naval and air base to protect what many believed to be its future oil and other explorations around it.

This had triggered alarm again among those countries laying overlapping claims over The Spratlys. As expected, US has to show its support against China's overtly unfair actions by a show of force in sending its navy to the region.

History has shown how US was incapable of fighting a long drawn war, far away from its shores. It was costly in terms of money and lives. Most US citizens would not support their country in fighting some countries' wars and losing their own lives in the process. US President is democratically elected, and they can only serve a maximum of two terms.

How can a President promise anything if he could not be in office soon after? This is the situation with the current President, Barack Obama, who will be ending his second term soon. A serving President has to account for his decisions, what more, where those involved heavy expenditure over a long period and would cost citizens' lives.

Compare and contrast this with an enemy like China, where its President has autocratic power over major decisions which in effect, means decisiveness, something so vital in any war.

Financially, it is more ironic, or even ludicrous, when China is now the biggest creditor of USA. Just imagine, your enemy financing you in developing or buying military hardware to fight with you! Without firing a single shot, China can easily withdraw its credit to US and probably cause its financial system to collapse.

My simplistic and naive suggestion in Facebook:

Malaysia, Philippines and Vietnam appear to have overlapping claims over Spratly Islands for years without resolving the issue. Now that China is claiming them, what can those countries do? Depend on US? US cannot sustain a long drawn war far away from its shores. China seems to have in place a 'permanent' warship with the newly reclaimed land. Why not let China be Big Brother instead of US, if it can promise not to have further territorial ambitions and can even offer economic aid to those countries willing to accept the conditions? This will avoid unnecessary war and bloodshed.

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