(CNN) -- Should we worry about mission creep? Only one week after President Obama said that he would not send combat troops to fight ISIS, Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, told the Senate that U.S. forces could "accompany Iraqi forces in attacks" if the situation deteriorated. As President Obama prepares to address the United Nations General Assembly this Wednesday, Americans are naturally wondering where this will all end. Some have raised the specter of Vietnam. After all, President John F. Kennedy sent fewer advisors to Vietnam during his presidency than President Obama is sending to Syria right now. James Carafano, a former Army officer at the American Heritage Foundation, said that "this is reminiscent of how we got involved in Vietnam."
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Some fear the fight against ISIS could expand via "mission creep"
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Julian Zelizer: Today's presidents constrained by factors that make another Vietnam unlikely
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Zelizer: Presidents no longer have the draft and immense budget resources for war
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He says public, chastened by recent wars, is in no mood for major military operations
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If the situation on the ground becomes worse, it would be difficult for the President to do nothing given that he has now acknowledged that @placeholder is a big problem that requires the intervention of the United States.
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Often, the legitimate and necessary warnings about what can go wrong overstate the risks of intervention and miss the ways in which our political environment has changed since the 1960s, in a way that makes the massive and ultimately futile ground war of @placeholder more difficult to replicate.
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The kind of wars @placeholder fights have also changed with new kinds of military technology that have developed along with the sophistication of special operation forces.
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A massive infusion of @placeholder troops won't have the impact that is needed, and in some ways given the opposition that exists toward western intervention, too many troops could make things worse by rallying Iraqis and Syrians against the United States rather than ISIS.
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But the fact is we are a long way away from @placeholder, and some of the institutional and cultural changes that have taken place -- as a result of that disastrous war -- have created a set of handcuffs on elected officials that won't be easily removed.